Re: 93 Jeep Grand Cherokee Cranks, But No Start
 

>"DougW" did pass the time by typing:
>Delays like that sound like thermal or leak current. Dirty connectors
>can cause similar problems.

I've been pulling and cleaning anything I find as I go along and no
change.

>Did you pull trouble codes when the lamp didn't light?

There are no trouble codes. The only thing the system is holding atm
is the battery has been disconnected because it was during tests.

>There are quite a few relays in the vehicle, apart from a smattering of
>relays under the dash, the primary center is located in the glovebox.
>It holds relays for Interior lights, power door locks, horn, power antenna,
>heated rear window, and the security alarm relay that flashes the
>lights and beeps the horn.

I'm not certain the clicking I occasionally here is related to this
problem or not, but since I'm not positive of whats behind the
glove/dash, I thought it a possible important note. I know the fuse
box has four circuit breakers in it and that one is for the alarm.
Since I can hear the rear window defrost relay "click" when I turn it
on and off, I was hoping the alarm circuit might do the same, but it's
the only one and it appears to be working.

>I'm running out of ideas, short of having a local dealer put a scantool
>on the system and run a full diagnosis. Most sensor faults are stored
>but on the 93 there is limited testing ability.

I've talked to a few people and the concensus is this isn't a senor
problem.I'm just hoping it's not the ECM.

>Failure to start can be the camshaft position sensor or the crankshaft
>position sensor. It can also be the coil. Anything that causes a no-start
>after a couple of engine cranks will turn off the ASD relay and remove power
>to the ignition coil. IF you have a test lamp, backprobe the coil wire that
>runs to the relay center. The lamp should light when you turn the key ON
>and stay lit while the engine cranks. It will go out if the engine doesn't start
>after a couple of revs. If it never comes on then there is another issue.
>(dead sensor/ECU fault) but most of those should be in the diagnositc codes.

But would any of these cause the dash "Check Engine" light to fail to
light or delay it to light?

>One thing you might try though is to clean the ECU connectors.
>(disconnect the battery + before doing this)
>
>You will have to remove the overflow bottle to gain access to the ECU.
>in the center of the large connector is a bolt, this has to come out.
>Turn it out, wiggle the connector, turn it out, wiggle the conector..etc.
>Don't use this bolt to force the connector on or off, it will crack the ECU!
>take the bolts out that hold the ECU to the firewall then rinse out the ecu
>with a plastic safe contact cleaner. Do the same to the connector. A bit
>of sandpaper on a stick can be used to clean off some of the connectors.
>Put some dilectric grease (sparkplug boot grease) on the connector before
>you put it back.
>
>Again, when you put the ECU back. Don't crank on the bolts that hold it down
>and don't use the connector bolt to suck the connector on. Press, tighen, press
>tighten, etc.
>
>Also, when cleaning the connector, don't forget to clean the wire side, that's
>where 90% of the buildup accumulates.

Is the ECU the only thing that sets the "Check Engine" on and into
it's diagnostic mode? I was hoping for some more light on these areas.

Re: 93 Jeep Grand Cherokee Cranks, But No Start
 

>"DougW" did pass the time by typing:
>Delays like that sound like thermal or leak current. Dirty connectors
>can cause similar problems.

I've been pulling and cleaning anything I find as I go along and no
change.

>Did you pull trouble codes when the lamp didn't light?

There are no trouble codes. The only thing the system is holding atm
is the battery has been disconnected because it was during tests.

>There are quite a few relays in the vehicle, apart from a smattering of
>relays under the dash, the primary center is located in the glovebox.
>It holds relays for Interior lights, power door locks, horn, power antenna,
>heated rear window, and the security alarm relay that flashes the
>lights and beeps the horn.

I'm not certain the clicking I occasionally here is related to this
problem or not, but since I'm not positive of whats behind the
glove/dash, I thought it a possible important note. I know the fuse
box has four circuit breakers in it and that one is for the alarm.
Since I can hear the rear window defrost relay "click" when I turn it
on and off, I was hoping the alarm circuit might do the same, but it's
the only one and it appears to be working.

>I'm running out of ideas, short of having a local dealer put a scantool
>on the system and run a full diagnosis. Most sensor faults are stored
>but on the 93 there is limited testing ability.

I've talked to a few people and the concensus is this isn't a senor
problem.I'm just hoping it's not the ECM.

>Failure to start can be the camshaft position sensor or the crankshaft
>position sensor. It can also be the coil. Anything that causes a no-start
>after a couple of engine cranks will turn off the ASD relay and remove power
>to the ignition coil. IF you have a test lamp, backprobe the coil wire that
>runs to the relay center. The lamp should light when you turn the key ON
>and stay lit while the engine cranks. It will go out if the engine doesn't start
>after a couple of revs. If it never comes on then there is another issue.
>(dead sensor/ECU fault) but most of those should be in the diagnositc codes.

But would any of these cause the dash "Check Engine" light to fail to
light or delay it to light?

>One thing you might try though is to clean the ECU connectors.
>(disconnect the battery + before doing this)
>
>You will have to remove the overflow bottle to gain access to the ECU.
>in the center of the large connector is a bolt, this has to come out.
>Turn it out, wiggle the connector, turn it out, wiggle the conector..etc.
>Don't use this bolt to force the connector on or off, it will crack the ECU!
>take the bolts out that hold the ECU to the firewall then rinse out the ecu
>with a plastic safe contact cleaner. Do the same to the connector. A bit
>of sandpaper on a stick can be used to clean off some of the connectors.
>Put some dilectric grease (sparkplug boot grease) on the connector before
>you put it back.
>
>Again, when you put the ECU back. Don't crank on the bolts that hold it down
>and don't use the connector bolt to suck the connector on. Press, tighen, press
>tighten, etc.
>
>Also, when cleaning the connector, don't forget to clean the wire side, that's
>where 90% of the buildup accumulates.

Is the ECU the only thing that sets the "Check Engine" on and into
it's diagnostic mode? I was hoping for some more light on these areas.

Re: 93 Jeep Grand Cherokee Cranks, But No Start
 

>"DougW" did pass the time by typing:
>Delays like that sound like thermal or leak current. Dirty connectors
>can cause similar problems.

I've been pulling and cleaning anything I find as I go along and no
change.

>Did you pull trouble codes when the lamp didn't light?

There are no trouble codes. The only thing the system is holding atm
is the battery has been disconnected because it was during tests.

>There are quite a few relays in the vehicle, apart from a smattering of
>relays under the dash, the primary center is located in the glovebox.
>It holds relays for Interior lights, power door locks, horn, power antenna,
>heated rear window, and the security alarm relay that flashes the
>lights and beeps the horn.

I'm not certain the clicking I occasionally here is related to this
problem or not, but since I'm not positive of whats behind the
glove/dash, I thought it a possible important note. I know the fuse
box has four circuit breakers in it and that one is for the alarm.
Since I can hear the rear window defrost relay "click" when I turn it
on and off, I was hoping the alarm circuit might do the same, but it's
the only one and it appears to be working.

>I'm running out of ideas, short of having a local dealer put a scantool
>on the system and run a full diagnosis. Most sensor faults are stored
>but on the 93 there is limited testing ability.

I've talked to a few people and the concensus is this isn't a senor
problem.I'm just hoping it's not the ECM.

>Failure to start can be the camshaft position sensor or the crankshaft
>position sensor. It can also be the coil. Anything that causes a no-start
>after a couple of engine cranks will turn off the ASD relay and remove power
>to the ignition coil. IF you have a test lamp, backprobe the coil wire that
>runs to the relay center. The lamp should light when you turn the key ON
>and stay lit while the engine cranks. It will go out if the engine doesn't start
>after a couple of revs. If it never comes on then there is another issue.
>(dead sensor/ECU fault) but most of those should be in the diagnositc codes.

But would any of these cause the dash "Check Engine" light to fail to
light or delay it to light?

>One thing you might try though is to clean the ECU connectors.
>(disconnect the battery + before doing this)
>
>You will have to remove the overflow bottle to gain access to the ECU.
>in the center of the large connector is a bolt, this has to come out.
>Turn it out, wiggle the connector, turn it out, wiggle the conector..etc.
>Don't use this bolt to force the connector on or off, it will crack the ECU!
>take the bolts out that hold the ECU to the firewall then rinse out the ecu
>with a plastic safe contact cleaner. Do the same to the connector. A bit
>of sandpaper on a stick can be used to clean off some of the connectors.
>Put some dilectric grease (sparkplug boot grease) on the connector before
>you put it back.
>
>Again, when you put the ECU back. Don't crank on the bolts that hold it down
>and don't use the connector bolt to suck the connector on. Press, tighen, press
>tighten, etc.
>
>Also, when cleaning the connector, don't forget to clean the wire side, that's
>where 90% of the buildup accumulates.

Is the ECU the only thing that sets the "Check Engine" on and into
it's diagnostic mode? I was hoping for some more light on these areas.

Re: 93 Jeep Grand Cherokee Cranks, But No Start
 

>On Thu, 23 Feb 2006 18:47:55 -0800, L.W.(ßill) ------ III wrote:
> Or a bad motor.
> God Bless America, Bill O|||||||O
>mailto:-------------------- http://www.----------.com/

Um, I think the fact that it consistantly starts when the "Check
Engine" light comes on on the dashboard indicates this is not a
mechanical problem. The engine is sound, cept for an oil change, and
no point in doing that until I can resolve this weird issue.

Re: 93 Jeep Grand Cherokee Cranks, But No Start
 

>On Thu, 23 Feb 2006 18:47:55 -0800, L.W.(ßill) ------ III wrote:
> Or a bad motor.
> God Bless America, Bill O|||||||O
>mailto:-------------------- http://www.----------.com/

Um, I think the fact that it consistantly starts when the "Check
Engine" light comes on on the dashboard indicates this is not a
mechanical problem. The engine is sound, cept for an oil change, and
no point in doing that until I can resolve this weird issue.

Re: 93 Jeep Grand Cherokee Cranks, But No Start
 

>On Thu, 23 Feb 2006 18:47:55 -0800, L.W.(ßill) ------ III wrote:
> Or a bad motor.
> God Bless America, Bill O|||||||O
>mailto:-------------------- http://www.----------.com/

Um, I think the fact that it consistantly starts when the "Check
Engine" light comes on on the dashboard indicates this is not a
mechanical problem. The engine is sound, cept for an oil change, and
no point in doing that until I can resolve this weird issue.

Re: 93 Jeep Grand Cherokee Cranks, But No Start
 

>On Thu, 23 Feb 2006 18:47:55 -0800, L.W.(ßill) ------ III wrote:
> Or a bad motor.
> God Bless America, Bill O|||||||O
>mailto:-------------------- http://www.----------.com/

Um, I think the fact that it consistantly starts when the "Check
Engine" light comes on on the dashboard indicates this is not a
mechanical problem. The engine is sound, cept for an oil change, and
no point in doing that until I can resolve this weird issue.

Re: 93 Jeep Grand Cherokee Cranks, But No Start
 

sounds like an intermittant connection.

could be a ground or a wire or a connector.

when the light is out, start wiggling wires.

Re: 93 Jeep Grand Cherokee Cranks, But No Start
 

sounds like an intermittant connection.

could be a ground or a wire or a connector.

when the light is out, start wiggling wires.

Re: 93 Jeep Grand Cherokee Cranks, But No Start
 

sounds like an intermittant connection.

could be a ground or a wire or a connector.

when the light is out, start wiggling wires.