Mike
the motor has 124k km on it.
When I took off the cap and rotor to replace them as the first step, the
rotor was pretty much eroded and the cap contacts and been pretty much wore
down so I got a crappy tire set along with the wires and threw them in.
The gas issue I'm guessing came from using shell gas about 4-5 years back
when they had the defective additive in it. I remember reading about a
class action suit for people getting their tanks cleaned.
I've been asking around and these are some suggestion from other people,
could you comment on their possibilities;
1. cam lobe flat spot
2. timing off, check marks on gears
3. leaky injector

Thanks for your reply. I pretty much have alot or respect for your
opinions.

--

Matt
0|||||||0
Tact is the ability to describe others as they see themselves
"Mike Romain" <romainm@sympatico.ca> wrote in message
news:4425599C.5B7456F@sympatico.ca...
> So something is up with the cold start circuit. Hmm....
>
> Ok, maybe two problems? Your first issue was with crap in the gas.
> Maybe you caused the second issue? Just a wild assed guess, but there
> are a bad run of distributor caps and rotors out on the market for the
> 4.0 engine. The rotors are too short which causes arcing and a cold
> engine miss for a while, then a miss all the time.
>
> Someone voiced the opinion the parts were made in two different
> factories or countries and they don't mate up together properly.
>
> Cold start misses can also be a bad or leaky plug wire. Even one just
> not pushed on tight. New ones can be bad too. I check them by spray
> misting them with water when it's dark out.
>
> Mike
>
> jeepr wrote:
> >
> > Mike
> > it has all been done since the problem occurred.
> > Like I said the fuel tank has been cleaned. the fuel pump and filter
> > replaced, injector flush, decarb the valves and all those components
> > replaced and nothing has fixed the problem, nothing showing on the read
outs
> > from all test boxes, and it only when cold' so can't be hoodlum's
> >
> > --
> >
> > Matt
> > 0|||||||0
> > Tact is the ability to describe others as they see themselves
> > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > news:44249A4A.DA8617F8@sympatico.ca...
> > > Was the maintenance done because of the miss? If not how much was
> > > before and after?
> > >
> > > Mike
> > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > 88 Cherokee 235 BFG AT's
> > > Canadian Off Road Trips Photos: Non members can still view!
> > > Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
> > > (More Off Road album links at bottom of the view page)
> > >
> > > jeepr wrote:
> > > >
> > > > 98 zj, 6 cyl. Runs rough after starting, when engine warm runs
smooth.
> > > > No check engine light. Have done maintenance in following order
> > > > 1. New plugs, new wires,new rotor,new cap
> > > > 1a. Took off fuel rail; full of crap, install fuel rail and do
injection
> > > > flush.
> > > > Worked great for about 3 weeks symptoms reappear.
> > > > 2. Drop fuel tank have steam cleaned, replace intank fuel pump, do a
> > > > injection flush from fuel tank forward.
> > > > Now have about $1200 invested in repairs and symptoms are still
there.
> > > >
> > > > Have hooked up the dealer pilot computer to record conditions when
> > symptoms
> > > > occur with nil negative pick ups
> > > > Dealer has done there chemical carbon cleaning of intake valves,
twice
> > > > dealer baroscopic the valves and there is no carbon on valves
> > > >
> > > > Have replaced the following with no positive results;
> > > > Crankshaft Position sensor
> > > > O2 sensors
> > > > Engine Coolant Sensor
> > > > The Main Computer
> > > >
> > > > No check engine light and runs rough when cold when first
accelerating
> > as
> > > > the accelerator is push vehicle will smooth out and
> > > > accelerate, like its missing on some cylinders.
> > > > Does not latch any code.
> > > >
> > > > Matt
> > > > 0|||||||0
> > > > Tact is the ability to describe others as they see themselves

 

It would be worth opening up the distributor cap and using a bright
light to see if it has tracked or arced already. CT did have those
defective sets in stock here in the Toronto area anyway. They were
informed about them, but no one there gives a crap.

The 4.0 engine is pretty solid. It has a chain for timing that doesn't
jump easy. Cam's don't grow new lobes when warm... ;-)

If it is goop plugging up an injector, the stuff might get real soft
when the engine warms up. You might need to do another clean on them.
Sometimes goop is 'very' hard to get all out of the lines.

It might be worth checking the plugs now to see if any look 'odd'. I
would run it for a little while it's it's rough, then shut it down while
still rough to see if one plug has a different burn mark on it.

Mine is running rough when damp and on choke right now and I checked the
plugs after moving it around in the driveway and found #2 and #5 to be
sooty. I am going to take my multimeter to those wires and compare the
resistance on them to #1. It should be the same per foot for all the
wires. My cap was clean, I checked that.

I have seen bad wires right out of the box as well. I have seen them
missing the crimp on the center core. The spark will still jump, but it
will miss when cold. This will show up on a plug visually usually.

I really think it will be crud still in an injector though.... Does the
4.0 have a cold start injector?

Mike

jeepr wrote:
>
> Mike
> the motor has 124k km on it.
> When I took off the cap and rotor to replace them as the first step, the
> rotor was pretty much eroded and the cap contacts and been pretty much wore
> down so I got a crappy tire set along with the wires and threw them in.
> The gas issue I'm guessing came from using shell gas about 4-5 years back
> when they had the defective additive in it. I remember reading about a
> class action suit for people getting their tanks cleaned.
> I've been asking around and these are some suggestion from other people,
> could you comment on their possibilities;
> 1. cam lobe flat spot
> 2. timing off, check marks on gears
> 3. leaky injector
>
> Thanks for your reply. I pretty much have alot or respect for your
> opinions.
>
> --
>
> Matt
> 0|||||||0
> Tact is the ability to describe others as they see themselves
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:4425599C.5B7456F@sympatico.ca...
> > So something is up with the cold start circuit. Hmm....
> >
> > Ok, maybe two problems? Your first issue was with crap in the gas.
> > Maybe you caused the second issue? Just a wild assed guess, but there
> > are a bad run of distributor caps and rotors out on the market for the
> > 4.0 engine. The rotors are too short which causes arcing and a cold
> > engine miss for a while, then a miss all the time.
> >
> > Someone voiced the opinion the parts were made in two different
> > factories or countries and they don't mate up together properly.
> >
> > Cold start misses can also be a bad or leaky plug wire. Even one just
> > not pushed on tight. New ones can be bad too. I check them by spray
> > misting them with water when it's dark out.
> >
> > Mike
> >
> > jeepr wrote:
> > >
> > > Mike
> > > it has all been done since the problem occurred.
> > > Like I said the fuel tank has been cleaned. the fuel pump and filter
> > > replaced, injector flush, decarb the valves and all those components
> > > replaced and nothing has fixed the problem, nothing showing on the read
> outs
> > > from all test boxes, and it only when cold' so can't be hoodlum's
> > >
> > > --
> > >
> > > Matt
> > > 0|||||||0
> > > Tact is the ability to describe others as they see themselves
> > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > news:44249A4A.DA8617F8@sympatico.ca...
> > > > Was the maintenance done because of the miss? If not how much was
> > > > before and after?
> > > >
> > > > Mike
> > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > 88 Cherokee 235 BFG AT's
> > > > Canadian Off Road Trips Photos: Non members can still view!
> > > > Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
> > > > (More Off Road album links at bottom of the view page)
> > > >
> > > > jeepr wrote:
> > > > >
> > > > > 98 zj, 6 cyl. Runs rough after starting, when engine warm runs
> smooth.
> > > > > No check engine light. Have done maintenance in following order
> > > > > 1. New plugs, new wires,new rotor,new cap
> > > > > 1a. Took off fuel rail; full of crap, install fuel rail and do
> injection
> > > > > flush.
> > > > > Worked great for about 3 weeks symptoms reappear.
> > > > > 2. Drop fuel tank have steam cleaned, replace intank fuel pump, do a
> > > > > injection flush from fuel tank forward.
> > > > > Now have about $1200 invested in repairs and symptoms are still
> there.
> > > > >
> > > > > Have hooked up the dealer pilot computer to record conditions when
> > > symptoms
> > > > > occur with nil negative pick ups
> > > > > Dealer has done there chemical carbon cleaning of intake valves,
> twice
> > > > > dealer baroscopic the valves and there is no carbon on valves
> > > > >
> > > > > Have replaced the following with no positive results;
> > > > > Crankshaft Position sensor
> > > > > O2 sensors
> > > > > Engine Coolant Sensor
> > > > > The Main Computer
> > > > >
> > > > > No check engine light and runs rough when cold when first
> accelerating
> > > as
> > > > > the accelerator is push vehicle will smooth out and
> > > > > accelerate, like its missing on some cylinders.
> > > > > Does not latch any code.
> > > > >
> > > > > Matt
> > > > > 0|||||||0
> > > > > Tact is the ability to describe others as they see themselves

 

It would be worth opening up the distributor cap and using a bright
light to see if it has tracked or arced already. CT did have those
defective sets in stock here in the Toronto area anyway. They were
informed about them, but no one there gives a crap.

The 4.0 engine is pretty solid. It has a chain for timing that doesn't
jump easy. Cam's don't grow new lobes when warm... ;-)

If it is goop plugging up an injector, the stuff might get real soft
when the engine warms up. You might need to do another clean on them.
Sometimes goop is 'very' hard to get all out of the lines.

It might be worth checking the plugs now to see if any look 'odd'. I
would run it for a little while it's it's rough, then shut it down while
still rough to see if one plug has a different burn mark on it.

Mine is running rough when damp and on choke right now and I checked the
plugs after moving it around in the driveway and found #2 and #5 to be
sooty. I am going to take my multimeter to those wires and compare the
resistance on them to #1. It should be the same per foot for all the
wires. My cap was clean, I checked that.

I have seen bad wires right out of the box as well. I have seen them
missing the crimp on the center core. The spark will still jump, but it
will miss when cold. This will show up on a plug visually usually.

I really think it will be crud still in an injector though.... Does the
4.0 have a cold start injector?

Mike

jeepr wrote:
>
> Mike
> the motor has 124k km on it.
> When I took off the cap and rotor to replace them as the first step, the
> rotor was pretty much eroded and the cap contacts and been pretty much wore
> down so I got a crappy tire set along with the wires and threw them in.
> The gas issue I'm guessing came from using shell gas about 4-5 years back
> when they had the defective additive in it. I remember reading about a
> class action suit for people getting their tanks cleaned.
> I've been asking around and these are some suggestion from other people,
> could you comment on their possibilities;
> 1. cam lobe flat spot
> 2. timing off, check marks on gears
> 3. leaky injector
>
> Thanks for your reply. I pretty much have alot or respect for your
> opinions.
>
> --
>
> Matt
> 0|||||||0
> Tact is the ability to describe others as they see themselves
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:4425599C.5B7456F@sympatico.ca...
> > So something is up with the cold start circuit. Hmm....
> >
> > Ok, maybe two problems? Your first issue was with crap in the gas.
> > Maybe you caused the second issue? Just a wild assed guess, but there
> > are a bad run of distributor caps and rotors out on the market for the
> > 4.0 engine. The rotors are too short which causes arcing and a cold
> > engine miss for a while, then a miss all the time.
> >
> > Someone voiced the opinion the parts were made in two different
> > factories or countries and they don't mate up together properly.
> >
> > Cold start misses can also be a bad or leaky plug wire. Even one just
> > not pushed on tight. New ones can be bad too. I check them by spray
> > misting them with water when it's dark out.
> >
> > Mike
> >
> > jeepr wrote:
> > >
> > > Mike
> > > it has all been done since the problem occurred.
> > > Like I said the fuel tank has been cleaned. the fuel pump and filter
> > > replaced, injector flush, decarb the valves and all those components
> > > replaced and nothing has fixed the problem, nothing showing on the read
> outs
> > > from all test boxes, and it only when cold' so can't be hoodlum's
> > >
> > > --
> > >
> > > Matt
> > > 0|||||||0
> > > Tact is the ability to describe others as they see themselves
> > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > news:44249A4A.DA8617F8@sympatico.ca...
> > > > Was the maintenance done because of the miss? If not how much was
> > > > before and after?
> > > >
> > > > Mike
> > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > 88 Cherokee 235 BFG AT's
> > > > Canadian Off Road Trips Photos: Non members can still view!
> > > > Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
> > > > (More Off Road album links at bottom of the view page)
> > > >
> > > > jeepr wrote:
> > > > >
> > > > > 98 zj, 6 cyl. Runs rough after starting, when engine warm runs
> smooth.
> > > > > No check engine light. Have done maintenance in following order
> > > > > 1. New plugs, new wires,new rotor,new cap
> > > > > 1a. Took off fuel rail; full of crap, install fuel rail and do
> injection
> > > > > flush.
> > > > > Worked great for about 3 weeks symptoms reappear.
> > > > > 2. Drop fuel tank have steam cleaned, replace intank fuel pump, do a
> > > > > injection flush from fuel tank forward.
> > > > > Now have about $1200 invested in repairs and symptoms are still
> there.
> > > > >
> > > > > Have hooked up the dealer pilot computer to record conditions when
> > > symptoms
> > > > > occur with nil negative pick ups
> > > > > Dealer has done there chemical carbon cleaning of intake valves,
> twice
> > > > > dealer baroscopic the valves and there is no carbon on valves
> > > > >
> > > > > Have replaced the following with no positive results;
> > > > > Crankshaft Position sensor
> > > > > O2 sensors
> > > > > Engine Coolant Sensor
> > > > > The Main Computer
> > > > >
> > > > > No check engine light and runs rough when cold when first
> accelerating
> > > as
> > > > > the accelerator is push vehicle will smooth out and
> > > > > accelerate, like its missing on some cylinders.
> > > > > Does not latch any code.
> > > > >
> > > > > Matt
> > > > > 0|||||||0
> > > > > Tact is the ability to describe others as they see themselves

 

It would be worth opening up the distributor cap and using a bright
light to see if it has tracked or arced already. CT did have those
defective sets in stock here in the Toronto area anyway. They were
informed about them, but no one there gives a crap.

The 4.0 engine is pretty solid. It has a chain for timing that doesn't
jump easy. Cam's don't grow new lobes when warm... ;-)

If it is goop plugging up an injector, the stuff might get real soft
when the engine warms up. You might need to do another clean on them.
Sometimes goop is 'very' hard to get all out of the lines.

It might be worth checking the plugs now to see if any look 'odd'. I
would run it for a little while it's it's rough, then shut it down while
still rough to see if one plug has a different burn mark on it.

Mine is running rough when damp and on choke right now and I checked the
plugs after moving it around in the driveway and found #2 and #5 to be
sooty. I am going to take my multimeter to those wires and compare the
resistance on them to #1. It should be the same per foot for all the
wires. My cap was clean, I checked that.

I have seen bad wires right out of the box as well. I have seen them
missing the crimp on the center core. The spark will still jump, but it
will miss when cold. This will show up on a plug visually usually.

I really think it will be crud still in an injector though.... Does the
4.0 have a cold start injector?

Mike

jeepr wrote:
>
> Mike
> the motor has 124k km on it.
> When I took off the cap and rotor to replace them as the first step, the
> rotor was pretty much eroded and the cap contacts and been pretty much wore
> down so I got a crappy tire set along with the wires and threw them in.
> The gas issue I'm guessing came from using shell gas about 4-5 years back
> when they had the defective additive in it. I remember reading about a
> class action suit for people getting their tanks cleaned.
> I've been asking around and these are some suggestion from other people,
> could you comment on their possibilities;
> 1. cam lobe flat spot
> 2. timing off, check marks on gears
> 3. leaky injector
>
> Thanks for your reply. I pretty much have alot or respect for your
> opinions.
>
> --
>
> Matt
> 0|||||||0
> Tact is the ability to describe others as they see themselves
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:4425599C.5B7456F@sympatico.ca...
> > So something is up with the cold start circuit. Hmm....
> >
> > Ok, maybe two problems? Your first issue was with crap in the gas.
> > Maybe you caused the second issue? Just a wild assed guess, but there
> > are a bad run of distributor caps and rotors out on the market for the
> > 4.0 engine. The rotors are too short which causes arcing and a cold
> > engine miss for a while, then a miss all the time.
> >
> > Someone voiced the opinion the parts were made in two different
> > factories or countries and they don't mate up together properly.
> >
> > Cold start misses can also be a bad or leaky plug wire. Even one just
> > not pushed on tight. New ones can be bad too. I check them by spray
> > misting them with water when it's dark out.
> >
> > Mike
> >
> > jeepr wrote:
> > >
> > > Mike
> > > it has all been done since the problem occurred.
> > > Like I said the fuel tank has been cleaned. the fuel pump and filter
> > > replaced, injector flush, decarb the valves and all those components
> > > replaced and nothing has fixed the problem, nothing showing on the read
> outs
> > > from all test boxes, and it only when cold' so can't be hoodlum's
> > >
> > > --
> > >
> > > Matt
> > > 0|||||||0
> > > Tact is the ability to describe others as they see themselves
> > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > news:44249A4A.DA8617F8@sympatico.ca...
> > > > Was the maintenance done because of the miss? If not how much was
> > > > before and after?
> > > >
> > > > Mike
> > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > 88 Cherokee 235 BFG AT's
> > > > Canadian Off Road Trips Photos: Non members can still view!
> > > > Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
> > > > (More Off Road album links at bottom of the view page)
> > > >
> > > > jeepr wrote:
> > > > >
> > > > > 98 zj, 6 cyl. Runs rough after starting, when engine warm runs
> smooth.
> > > > > No check engine light. Have done maintenance in following order
> > > > > 1. New plugs, new wires,new rotor,new cap
> > > > > 1a. Took off fuel rail; full of crap, install fuel rail and do
> injection
> > > > > flush.
> > > > > Worked great for about 3 weeks symptoms reappear.
> > > > > 2. Drop fuel tank have steam cleaned, replace intank fuel pump, do a
> > > > > injection flush from fuel tank forward.
> > > > > Now have about $1200 invested in repairs and symptoms are still
> there.
> > > > >
> > > > > Have hooked up the dealer pilot computer to record conditions when
> > > symptoms
> > > > > occur with nil negative pick ups
> > > > > Dealer has done there chemical carbon cleaning of intake valves,
> twice
> > > > > dealer baroscopic the valves and there is no carbon on valves
> > > > >
> > > > > Have replaced the following with no positive results;
> > > > > Crankshaft Position sensor
> > > > > O2 sensors
> > > > > Engine Coolant Sensor
> > > > > The Main Computer
> > > > >
> > > > > No check engine light and runs rough when cold when first
> accelerating
> > > as
> > > > > the accelerator is push vehicle will smooth out and
> > > > > accelerate, like its missing on some cylinders.
> > > > > Does not latch any code.
> > > > >
> > > > > Matt
> > > > > 0|||||||0
> > > > > Tact is the ability to describe others as they see themselves

 

Mike Romain did pass the time by typing:
> It would be worth opening up the distributor cap and using a bright
> light to see if it has tracked or arced already. CT did have those
> defective sets in stock here in the Toronto area anyway. They were
> informed about them, but no one there gives a crap.

Or look to see if it's like mine was when the bushing was gone
and oil was coming up the shaft. That causes all sorts of carbon arcing.
http://revbeergoggles.com/distributor/
Don't discount the pinprick hole that can happen under the rotor.
I beat my head against the wall trying to figure out why my 305 wouldn't
fire. Turns out it was arcing straight through the rotor.

> If it is goop plugging up an injector, the stuff might get real soft
> when the engine warms up. You might need to do another clean on them.
> Sometimes goop is 'very' hard to get all out of the lines.

Tell me about it. In my old Chevy it took an air compressor and several
runs with solvent to get the fuel lines clean. Too bad there isn't an
easy way to install a second filter just before the rail.

> Mine is running rough when damp and on choke right now and I checked the
> plugs after moving it around in the driveway and found #2 and #5 to be
> sooty. I am going to take my multimeter to those wires and compare the
> resistance on them to #1. It should be the same per foot for all the
> wires. My cap was clean, I checked that.

on the non direct-fire 4.0, 2 and 5 have the shortest cables and when
the coil is going you will probably see 1,6 then 4,5 with more carbon/
unburned fuel buildup. (that's what mine looked like at least)
Sorta makes sense as the longer wires will take some energy away and
with a marginal coil they might not get a full spark as soon as they should.
cyl 1 and 6 run the coolest on that engine.
If it was 5 and 6 I'd suspect the vac source was sucking in oil.
You can't get an oil feed to 1, 2, or 3 from the intake rail vac sources.

http://revbeergoggles.com/Fixes/engi...plug-wires.jpg

> I have seen bad wires right out of the box as well. I have seen them
> missing the crimp on the center core. The spark will still jump, but it
> will miss when cold. This will show up on a plug visually usually.

Tell me about it. I've had the dang things fall apart in my hands before.
Currently I use Bosch and they have held up well to abuse.

> I really think it will be crud still in an injector though.... Does the
> 4.0 have a cold start injector?

Nope. It's got a cold start mode, but that just bypasses things like the
O2 sensor.
http://revbeergoggles.com/Fixes/diagnostics.html
goes over the sensor used for each mode.


One thing to try is to start the engine then disconnect the IAC connector.
If the engine smooths out then your looking at a sensor problem or a dirty
IAC. (Idle Air Controller) For sensors, that can be the MAP sensor (expensive
doodad) or (camshaft position sensor in the distributor)

> Mike
>
> jeepr wrote:
>>
>> Mike
>> the motor has 124k km on it.
>> When I took off the cap and rotor to replace them as the first step, the
>> rotor was pretty much eroded and the cap contacts and been pretty much wore
>> down so I got a crappy tire set along with the wires and threw them in.
>> The gas issue I'm guessing came from using shell gas about 4-5 years back
>> when they had the defective additive in it. I remember reading about a
>> class action suit for people getting their tanks cleaned.
>> I've been asking around and these are some suggestion from other people,
>> could you comment on their possibilities;
>> 1. cam lobe flat spot
>> 2. timing off, check marks on gears
>> 3. leaky injector
>>
>> Thanks for your reply. I pretty much have alot or respect for your
>> opinions.

<snip>

--
DougW

 

Mike Romain did pass the time by typing:
> It would be worth opening up the distributor cap and using a bright
> light to see if it has tracked or arced already. CT did have those
> defective sets in stock here in the Toronto area anyway. They were
> informed about them, but no one there gives a crap.

Or look to see if it's like mine was when the bushing was gone
and oil was coming up the shaft. That causes all sorts of carbon arcing.
http://revbeergoggles.com/distributor/
Don't discount the pinprick hole that can happen under the rotor.
I beat my head against the wall trying to figure out why my 305 wouldn't
fire. Turns out it was arcing straight through the rotor.

> If it is goop plugging up an injector, the stuff might get real soft
> when the engine warms up. You might need to do another clean on them.
> Sometimes goop is 'very' hard to get all out of the lines.

Tell me about it. In my old Chevy it took an air compressor and several
runs with solvent to get the fuel lines clean. Too bad there isn't an
easy way to install a second filter just before the rail.

> Mine is running rough when damp and on choke right now and I checked the
> plugs after moving it around in the driveway and found #2 and #5 to be
> sooty. I am going to take my multimeter to those wires and compare the
> resistance on them to #1. It should be the same per foot for all the
> wires. My cap was clean, I checked that.

on the non direct-fire 4.0, 2 and 5 have the shortest cables and when
the coil is going you will probably see 1,6 then 4,5 with more carbon/
unburned fuel buildup. (that's what mine looked like at least)
Sorta makes sense as the longer wires will take some energy away and
with a marginal coil they might not get a full spark as soon as they should.
cyl 1 and 6 run the coolest on that engine.
If it was 5 and 6 I'd suspect the vac source was sucking in oil.
You can't get an oil feed to 1, 2, or 3 from the intake rail vac sources.

http://revbeergoggles.com/Fixes/engi...plug-wires.jpg

> I have seen bad wires right out of the box as well. I have seen them
> missing the crimp on the center core. The spark will still jump, but it
> will miss when cold. This will show up on a plug visually usually.

Tell me about it. I've had the dang things fall apart in my hands before.
Currently I use Bosch and they have held up well to abuse.

> I really think it will be crud still in an injector though.... Does the
> 4.0 have a cold start injector?

Nope. It's got a cold start mode, but that just bypasses things like the
O2 sensor.
http://revbeergoggles.com/Fixes/diagnostics.html
goes over the sensor used for each mode.


One thing to try is to start the engine then disconnect the IAC connector.
If the engine smooths out then your looking at a sensor problem or a dirty
IAC. (Idle Air Controller) For sensors, that can be the MAP sensor (expensive
doodad) or (camshaft position sensor in the distributor)

> Mike
>
> jeepr wrote:
>>
>> Mike
>> the motor has 124k km on it.
>> When I took off the cap and rotor to replace them as the first step, the
>> rotor was pretty much eroded and the cap contacts and been pretty much wore
>> down so I got a crappy tire set along with the wires and threw them in.
>> The gas issue I'm guessing came from using shell gas about 4-5 years back
>> when they had the defective additive in it. I remember reading about a
>> class action suit for people getting their tanks cleaned.
>> I've been asking around and these are some suggestion from other people,
>> could you comment on their possibilities;
>> 1. cam lobe flat spot
>> 2. timing off, check marks on gears
>> 3. leaky injector
>>
>> Thanks for your reply. I pretty much have alot or respect for your
>> opinions.

<snip>

--
DougW

 

Mike Romain did pass the time by typing:
> It would be worth opening up the distributor cap and using a bright
> light to see if it has tracked or arced already. CT did have those
> defective sets in stock here in the Toronto area anyway. They were
> informed about them, but no one there gives a crap.

Or look to see if it's like mine was when the bushing was gone
and oil was coming up the shaft. That causes all sorts of carbon arcing.
http://revbeergoggles.com/distributor/
Don't discount the pinprick hole that can happen under the rotor.
I beat my head against the wall trying to figure out why my 305 wouldn't
fire. Turns out it was arcing straight through the rotor.

> If it is goop plugging up an injector, the stuff might get real soft
> when the engine warms up. You might need to do another clean on them.
> Sometimes goop is 'very' hard to get all out of the lines.

Tell me about it. In my old Chevy it took an air compressor and several
runs with solvent to get the fuel lines clean. Too bad there isn't an
easy way to install a second filter just before the rail.

> Mine is running rough when damp and on choke right now and I checked the
> plugs after moving it around in the driveway and found #2 and #5 to be
> sooty. I am going to take my multimeter to those wires and compare the
> resistance on them to #1. It should be the same per foot for all the
> wires. My cap was clean, I checked that.

on the non direct-fire 4.0, 2 and 5 have the shortest cables and when
the coil is going you will probably see 1,6 then 4,5 with more carbon/
unburned fuel buildup. (that's what mine looked like at least)
Sorta makes sense as the longer wires will take some energy away and
with a marginal coil they might not get a full spark as soon as they should.
cyl 1 and 6 run the coolest on that engine.
If it was 5 and 6 I'd suspect the vac source was sucking in oil.
You can't get an oil feed to 1, 2, or 3 from the intake rail vac sources.

http://revbeergoggles.com/Fixes/engi...plug-wires.jpg

> I have seen bad wires right out of the box as well. I have seen them
> missing the crimp on the center core. The spark will still jump, but it
> will miss when cold. This will show up on a plug visually usually.

Tell me about it. I've had the dang things fall apart in my hands before.
Currently I use Bosch and they have held up well to abuse.

> I really think it will be crud still in an injector though.... Does the
> 4.0 have a cold start injector?

Nope. It's got a cold start mode, but that just bypasses things like the
O2 sensor.
http://revbeergoggles.com/Fixes/diagnostics.html
goes over the sensor used for each mode.


One thing to try is to start the engine then disconnect the IAC connector.
If the engine smooths out then your looking at a sensor problem or a dirty
IAC. (Idle Air Controller) For sensors, that can be the MAP sensor (expensive
doodad) or (camshaft position sensor in the distributor)

> Mike
>
> jeepr wrote:
>>
>> Mike
>> the motor has 124k km on it.
>> When I took off the cap and rotor to replace them as the first step, the
>> rotor was pretty much eroded and the cap contacts and been pretty much wore
>> down so I got a crappy tire set along with the wires and threw them in.
>> The gas issue I'm guessing came from using shell gas about 4-5 years back
>> when they had the defective additive in it. I remember reading about a
>> class action suit for people getting their tanks cleaned.
>> I've been asking around and these are some suggestion from other people,
>> could you comment on their possibilities;
>> 1. cam lobe flat spot
>> 2. timing off, check marks on gears
>> 3. leaky injector
>>
>> Thanks for your reply. I pretty much have alot or respect for your
>> opinions.

<snip>

--
DougW

 

If you think the fuel rail and injectors may be dirty you can go to a shop
that services Diesel truck injectors and they will have ultrasonic tanks
large enough to drop the fuel rail into while they clean and service your
injectors.


"Mike Romain" <romainm@sympatico.ca> wrote in message
news:44258A82.DD8CCB54@sympatico.ca...
> It would be worth opening up the distributor cap and using a bright
> light to see if it has tracked or arced already. CT did have those
> defective sets in stock here in the Toronto area anyway. They were
> informed about them, but no one there gives a crap.
>
> The 4.0 engine is pretty solid. It has a chain for timing that doesn't
> jump easy. Cam's don't grow new lobes when warm... ;-)
>
> If it is goop plugging up an injector, the stuff might get real soft
> when the engine warms up. You might need to do another clean on them.
> Sometimes goop is 'very' hard to get all out of the lines.
>
> It might be worth checking the plugs now to see if any look 'odd'. I
> would run it for a little while it's it's rough, then shut it down while
> still rough to see if one plug has a different burn mark on it.
>
> Mine is running rough when damp and on choke right now and I checked the
> plugs after moving it around in the driveway and found #2 and #5 to be
> sooty. I am going to take my multimeter to those wires and compare the
> resistance on them to #1. It should be the same per foot for all the
> wires. My cap was clean, I checked that.
>
> I have seen bad wires right out of the box as well. I have seen them
> missing the crimp on the center core. The spark will still jump, but it
> will miss when cold. This will show up on a plug visually usually.
>
> I really think it will be crud still in an injector though.... Does the
> 4.0 have a cold start injector?
>
> Mike
>
> jeepr wrote:
>>
>> Mike
>> the motor has 124k km on it.
>> When I took off the cap and rotor to replace them as the first step, the
>> rotor was pretty much eroded and the cap contacts and been pretty much
>> wore
>> down so I got a crappy tire set along with the wires and threw them in.
>> The gas issue I'm guessing came from using shell gas about 4-5 years back
>> when they had the defective additive in it. I remember reading about a
>> class action suit for people getting their tanks cleaned.
>> I've been asking around and these are some suggestion from other people,
>> could you comment on their possibilities;
>> 1. cam lobe flat spot
>> 2. timing off, check marks on gears
>> 3. leaky injector
>>
>> Thanks for your reply. I pretty much have alot or respect for your
>> opinions.
>>
>> --
>>
>> Matt
>> 0|||||||0
>> Tact is the ability to describe others as they see themselves
>> "Mike Romain" <romainm@sympatico.ca> wrote in message
>> news:4425599C.5B7456F@sympatico.ca...
>> > So something is up with the cold start circuit. Hmm....
>> >
>> > Ok, maybe two problems? Your first issue was with crap in the gas.
>> > Maybe you caused the second issue? Just a wild assed guess, but there
>> > are a bad run of distributor caps and rotors out on the market for the
>> > 4.0 engine. The rotors are too short which causes arcing and a cold
>> > engine miss for a while, then a miss all the time.
>> >
>> > Someone voiced the opinion the parts were made in two different
>> > factories or countries and they don't mate up together properly.
>> >
>> > Cold start misses can also be a bad or leaky plug wire. Even one just
>> > not pushed on tight. New ones can be bad too. I check them by spray
>> > misting them with water when it's dark out.
>> >
>> > Mike
>> >
>> > jeepr wrote:
>> > >
>> > > Mike
>> > > it has all been done since the problem occurred.
>> > > Like I said the fuel tank has been cleaned. the fuel pump and filter
>> > > replaced, injector flush, decarb the valves and all those components
>> > > replaced and nothing has fixed the problem, nothing showing on the
>> > > read
>> outs
>> > > from all test boxes, and it only when cold' so can't be hoodlum's
>> > >
>> > > --
>> > >
>> > > Matt
>> > > 0|||||||0
>> > > Tact is the ability to describe others as they see themselves
>> > > "Mike Romain" <romainm@sympatico.ca> wrote in message
>> > > news:44249A4A.DA8617F8@sympatico.ca...
>> > > > Was the maintenance done because of the miss? If not how much was
>> > > > before and after?
>> > > >
>> > > > Mike
>> > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>> > > > 88 Cherokee 235 BFG AT's
>> > > > Canadian Off Road Trips Photos: Non members can still view!
>> > > > Jan/06
>> > > > http://www.imagestation.com/album/pi...?id=2115147590
>> > > > (More Off Road album links at bottom of the view page)
>> > > >
>> > > > jeepr wrote:
>> > > > >
>> > > > > 98 zj, 6 cyl. Runs rough after starting, when engine warm runs
>> smooth.
>> > > > > No check engine light. Have done maintenance in following order
>> > > > > 1. New plugs, new wires,new rotor,new cap
>> > > > > 1a. Took off fuel rail; full of crap, install fuel rail and do
>> injection
>> > > > > flush.
>> > > > > Worked great for about 3 weeks symptoms reappear.
>> > > > > 2. Drop fuel tank have steam cleaned, replace intank fuel pump,
>> > > > > do a
>> > > > > injection flush from fuel tank forward.
>> > > > > Now have about $1200 invested in repairs and symptoms are still
>> there.
>> > > > >
>> > > > > Have hooked up the dealer pilot computer to record conditions
>> > > > > when
>> > > symptoms
>> > > > > occur with nil negative pick ups
>> > > > > Dealer has done there chemical carbon cleaning of intake valves,
>> twice
>> > > > > dealer baroscopic the valves and there is no carbon on valves
>> > > > >
>> > > > > Have replaced the following with no positive results;
>> > > > > Crankshaft Position sensor
>> > > > > O2 sensors
>> > > > > Engine Coolant Sensor
>> > > > > The Main Computer
>> > > > >
>> > > > > No check engine light and runs rough when cold when first
>> accelerating
>> > > as
>> > > > > the accelerator is push vehicle will smooth out and
>> > > > > accelerate, like its missing on some cylinders.
>> > > > > Does not latch any code.
>> > > > >
>> > > > > Matt
>> > > > > 0|||||||0
>> > > > > Tact is the ability to describe others as they see themselves

 

If you think the fuel rail and injectors may be dirty you can go to a shop
that services Diesel truck injectors and they will have ultrasonic tanks
large enough to drop the fuel rail into while they clean and service your
injectors.


"Mike Romain" <romainm@sympatico.ca> wrote in message
news:44258A82.DD8CCB54@sympatico.ca...
> It would be worth opening up the distributor cap and using a bright
> light to see if it has tracked or arced already. CT did have those
> defective sets in stock here in the Toronto area anyway. They were
> informed about them, but no one there gives a crap.
>
> The 4.0 engine is pretty solid. It has a chain for timing that doesn't
> jump easy. Cam's don't grow new lobes when warm... ;-)
>
> If it is goop plugging up an injector, the stuff might get real soft
> when the engine warms up. You might need to do another clean on them.
> Sometimes goop is 'very' hard to get all out of the lines.
>
> It might be worth checking the plugs now to see if any look 'odd'. I
> would run it for a little while it's it's rough, then shut it down while
> still rough to see if one plug has a different burn mark on it.
>
> Mine is running rough when damp and on choke right now and I checked the
> plugs after moving it around in the driveway and found #2 and #5 to be
> sooty. I am going to take my multimeter to those wires and compare the
> resistance on them to #1. It should be the same per foot for all the
> wires. My cap was clean, I checked that.
>
> I have seen bad wires right out of the box as well. I have seen them
> missing the crimp on the center core. The spark will still jump, but it
> will miss when cold. This will show up on a plug visually usually.
>
> I really think it will be crud still in an injector though.... Does the
> 4.0 have a cold start injector?
>
> Mike
>
> jeepr wrote:
>>
>> Mike
>> the motor has 124k km on it.
>> When I took off the cap and rotor to replace them as the first step, the
>> rotor was pretty much eroded and the cap contacts and been pretty much
>> wore
>> down so I got a crappy tire set along with the wires and threw them in.
>> The gas issue I'm guessing came from using shell gas about 4-5 years back
>> when they had the defective additive in it. I remember reading about a
>> class action suit for people getting their tanks cleaned.
>> I've been asking around and these are some suggestion from other people,
>> could you comment on their possibilities;
>> 1. cam lobe flat spot
>> 2. timing off, check marks on gears
>> 3. leaky injector
>>
>> Thanks for your reply. I pretty much have alot or respect for your
>> opinions.
>>
>> --
>>
>> Matt
>> 0|||||||0
>> Tact is the ability to describe others as they see themselves
>> "Mike Romain" <romainm@sympatico.ca> wrote in message
>> news:4425599C.5B7456F@sympatico.ca...
>> > So something is up with the cold start circuit. Hmm....
>> >
>> > Ok, maybe two problems? Your first issue was with crap in the gas.
>> > Maybe you caused the second issue? Just a wild assed guess, but there
>> > are a bad run of distributor caps and rotors out on the market for the
>> > 4.0 engine. The rotors are too short which causes arcing and a cold
>> > engine miss for a while, then a miss all the time.
>> >
>> > Someone voiced the opinion the parts were made in two different
>> > factories or countries and they don't mate up together properly.
>> >
>> > Cold start misses can also be a bad or leaky plug wire. Even one just
>> > not pushed on tight. New ones can be bad too. I check them by spray
>> > misting them with water when it's dark out.
>> >
>> > Mike
>> >
>> > jeepr wrote:
>> > >
>> > > Mike
>> > > it has all been done since the problem occurred.
>> > > Like I said the fuel tank has been cleaned. the fuel pump and filter
>> > > replaced, injector flush, decarb the valves and all those components
>> > > replaced and nothing has fixed the problem, nothing showing on the
>> > > read
>> outs
>> > > from all test boxes, and it only when cold' so can't be hoodlum's
>> > >
>> > > --
>> > >
>> > > Matt
>> > > 0|||||||0
>> > > Tact is the ability to describe others as they see themselves
>> > > "Mike Romain" <romainm@sympatico.ca> wrote in message
>> > > news:44249A4A.DA8617F8@sympatico.ca...
>> > > > Was the maintenance done because of the miss? If not how much was
>> > > > before and after?
>> > > >
>> > > > Mike
>> > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>> > > > 88 Cherokee 235 BFG AT's
>> > > > Canadian Off Road Trips Photos: Non members can still view!
>> > > > Jan/06
>> > > > http://www.imagestation.com/album/pi...?id=2115147590
>> > > > (More Off Road album links at bottom of the view page)
>> > > >
>> > > > jeepr wrote:
>> > > > >
>> > > > > 98 zj, 6 cyl. Runs rough after starting, when engine warm runs
>> smooth.
>> > > > > No check engine light. Have done maintenance in following order
>> > > > > 1. New plugs, new wires,new rotor,new cap
>> > > > > 1a. Took off fuel rail; full of crap, install fuel rail and do
>> injection
>> > > > > flush.
>> > > > > Worked great for about 3 weeks symptoms reappear.
>> > > > > 2. Drop fuel tank have steam cleaned, replace intank fuel pump,
>> > > > > do a
>> > > > > injection flush from fuel tank forward.
>> > > > > Now have about $1200 invested in repairs and symptoms are still
>> there.
>> > > > >
>> > > > > Have hooked up the dealer pilot computer to record conditions
>> > > > > when
>> > > symptoms
>> > > > > occur with nil negative pick ups
>> > > > > Dealer has done there chemical carbon cleaning of intake valves,
>> twice
>> > > > > dealer baroscopic the valves and there is no carbon on valves
>> > > > >
>> > > > > Have replaced the following with no positive results;
>> > > > > Crankshaft Position sensor
>> > > > > O2 sensors
>> > > > > Engine Coolant Sensor
>> > > > > The Main Computer
>> > > > >
>> > > > > No check engine light and runs rough when cold when first
>> accelerating
>> > > as
>> > > > > the accelerator is push vehicle will smooth out and
>> > > > > accelerate, like its missing on some cylinders.
>> > > > > Does not latch any code.
>> > > > >
>> > > > > Matt
>> > > > > 0|||||||0
>> > > > > Tact is the ability to describe others as they see themselves

 

If you think the fuel rail and injectors may be dirty you can go to a shop
that services Diesel truck injectors and they will have ultrasonic tanks
large enough to drop the fuel rail into while they clean and service your
injectors.


"Mike Romain" <romainm@sympatico.ca> wrote in message
news:44258A82.DD8CCB54@sympatico.ca...
> It would be worth opening up the distributor cap and using a bright
> light to see if it has tracked or arced already. CT did have those
> defective sets in stock here in the Toronto area anyway. They were
> informed about them, but no one there gives a crap.
>
> The 4.0 engine is pretty solid. It has a chain for timing that doesn't
> jump easy. Cam's don't grow new lobes when warm... ;-)
>
> If it is goop plugging up an injector, the stuff might get real soft
> when the engine warms up. You might need to do another clean on them.
> Sometimes goop is 'very' hard to get all out of the lines.
>
> It might be worth checking the plugs now to see if any look 'odd'. I
> would run it for a little while it's it's rough, then shut it down while
> still rough to see if one plug has a different burn mark on it.
>
> Mine is running rough when damp and on choke right now and I checked the
> plugs after moving it around in the driveway and found #2 and #5 to be
> sooty. I am going to take my multimeter to those wires and compare the
> resistance on them to #1. It should be the same per foot for all the
> wires. My cap was clean, I checked that.
>
> I have seen bad wires right out of the box as well. I have seen them
> missing the crimp on the center core. The spark will still jump, but it
> will miss when cold. This will show up on a plug visually usually.
>
> I really think it will be crud still in an injector though.... Does the
> 4.0 have a cold start injector?
>
> Mike
>
> jeepr wrote:
>>
>> Mike
>> the motor has 124k km on it.
>> When I took off the cap and rotor to replace them as the first step, the
>> rotor was pretty much eroded and the cap contacts and been pretty much
>> wore
>> down so I got a crappy tire set along with the wires and threw them in.
>> The gas issue I'm guessing came from using shell gas about 4-5 years back
>> when they had the defective additive in it. I remember reading about a
>> class action suit for people getting their tanks cleaned.
>> I've been asking around and these are some suggestion from other people,
>> could you comment on their possibilities;
>> 1. cam lobe flat spot
>> 2. timing off, check marks on gears
>> 3. leaky injector
>>
>> Thanks for your reply. I pretty much have alot or respect for your
>> opinions.
>>
>> --
>>
>> Matt
>> 0|||||||0
>> Tact is the ability to describe others as they see themselves
>> "Mike Romain" <romainm@sympatico.ca> wrote in message
>> news:4425599C.5B7456F@sympatico.ca...
>> > So something is up with the cold start circuit. Hmm....
>> >
>> > Ok, maybe two problems? Your first issue was with crap in the gas.
>> > Maybe you caused the second issue? Just a wild assed guess, but there
>> > are a bad run of distributor caps and rotors out on the market for the
>> > 4.0 engine. The rotors are too short which causes arcing and a cold
>> > engine miss for a while, then a miss all the time.
>> >
>> > Someone voiced the opinion the parts were made in two different
>> > factories or countries and they don't mate up together properly.
>> >
>> > Cold start misses can also be a bad or leaky plug wire. Even one just
>> > not pushed on tight. New ones can be bad too. I check them by spray
>> > misting them with water when it's dark out.
>> >
>> > Mike
>> >
>> > jeepr wrote:
>> > >
>> > > Mike
>> > > it has all been done since the problem occurred.
>> > > Like I said the fuel tank has been cleaned. the fuel pump and filter
>> > > replaced, injector flush, decarb the valves and all those components
>> > > replaced and nothing has fixed the problem, nothing showing on the
>> > > read
>> outs
>> > > from all test boxes, and it only when cold' so can't be hoodlum's
>> > >
>> > > --
>> > >
>> > > Matt
>> > > 0|||||||0
>> > > Tact is the ability to describe others as they see themselves
>> > > "Mike Romain" <romainm@sympatico.ca> wrote in message
>> > > news:44249A4A.DA8617F8@sympatico.ca...
>> > > > Was the maintenance done because of the miss? If not how much was
>> > > > before and after?
>> > > >
>> > > > Mike
>> > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>> > > > 88 Cherokee 235 BFG AT's
>> > > > Canadian Off Road Trips Photos: Non members can still view!
>> > > > Jan/06
>> > > > http://www.imagestation.com/album/pi...?id=2115147590
>> > > > (More Off Road album links at bottom of the view page)
>> > > >
>> > > > jeepr wrote:
>> > > > >
>> > > > > 98 zj, 6 cyl. Runs rough after starting, when engine warm runs
>> smooth.
>> > > > > No check engine light. Have done maintenance in following order
>> > > > > 1. New plugs, new wires,new rotor,new cap
>> > > > > 1a. Took off fuel rail; full of crap, install fuel rail and do
>> injection
>> > > > > flush.
>> > > > > Worked great for about 3 weeks symptoms reappear.
>> > > > > 2. Drop fuel tank have steam cleaned, replace intank fuel pump,
>> > > > > do a
>> > > > > injection flush from fuel tank forward.
>> > > > > Now have about $1200 invested in repairs and symptoms are still
>> there.
>> > > > >
>> > > > > Have hooked up the dealer pilot computer to record conditions
>> > > > > when
>> > > symptoms
>> > > > > occur with nil negative pick ups
>> > > > > Dealer has done there chemical carbon cleaning of intake valves,
>> twice
>> > > > > dealer baroscopic the valves and there is no carbon on valves
>> > > > >
>> > > > > Have replaced the following with no positive results;
>> > > > > Crankshaft Position sensor
>> > > > > O2 sensors
>> > > > > Engine Coolant Sensor
>> > > > > The Main Computer
>> > > > >
>> > > > > No check engine light and runs rough when cold when first
>> accelerating
>> > > as
>> > > > > the accelerator is push vehicle will smooth out and
>> > > > > accelerate, like its missing on some cylinders.
>> > > > > Does not latch any code.
>> > > > >
>> > > > > Matt
>> > > > > 0|||||||0
>> > > > > Tact is the ability to describe others as they see themselves