I have had more than one fail with NO external sign of anything wrong.
Swapping modules is the only real way of checking for a bad ignition module.
<pomerom@yahoo.com> wrote in message
news:uume00l7o9ivdnu9vkgudm61im70p048bd@4ax.com...
> Thanks for the suggestion.
>
> I inspected it closely. No obvious sign of any problem.
>
> So still stumped ......
>
> Mike
>
> On 15 Jan 2004 05:05:34 GMT, onlyinajeepcj7@aol.com (Onlyinajeepcj7)
> wrote:
>
> >also check the ign box (drivers inner fender under water bottle) if back
is
> >melted, it is bad or on it's way out.
>
> Michael Pomeroy

 

A bad ground comes to mind next, then a bad ignition module.

I test the grounds with a booster cable. I run it from the battery
negative to the engine block and see what happens, if the same I then
tag the distributor itself with the booster cable. (I have seen a few
distributors loose their ground due to surface rust)

If still no joy I then tag the firewall with the booster cable and then
the ignition module itself. The module needs a good ground or it will
try and steal one through the distributor.

How is the fuel filter? A plugged up one can starve the carb for fuel
at idle and cause the inductive miss you see. When the pump comes up in
speed, it can force gas through a partially plugged filter.

So can a fuel filter that is in upside down. If upside down, it will
pump too much gas back to the tank at idle and can starve the carb for
fuel.

Just a few more thoughts for you...

Mike

pomerom@yahoo.com wrote:
>
> Mike,
>
> Didn't say this in the initial posting because I didn't think it
> relevant, but original carb is gone and there is a Weber on there now.
>
> And I don't know for sure, but looking back and thinking back I
> believe I've had this problem for some time -- even when the original
> carburator was still in place. (The Scrambler is driven on an
> irregular basis.)
>
> Still no joy -- more suggestions please ......
>
> Mike
>
> On Thu, 15 Jan 2004 09:44:58 -0500, Mike Romain <romainm@sympatico.ca>
> wrote:
>
> >I got suckered with those symptoms and an inductive timing light and
> >went after parts.
> >
> >It was plugged idle tubes in the carb. The lack of or wrong amount of
> >gas reaching the plugs affected the timing light implying a spark
> >problem.
> >
> >I figured it out after there was nothing electrical left to change...
> >
> >Here is a link on the idle tubes and the fix for them. I can fix them
> >from the top in about 15 minutes now that I know how to do it.
> >
> >http://www.off-road.com/jeep/tech/engine/carter.html
> >
> >Also a kit for that carb is only twenty bucks or so and should be done
> >with every major tuneup or spark plug change.
> >
> >Mike
> >86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> >88 Cherokee 235 BFG AT's
> >
> >pomerom@yahoo.com wrote:
> >>
> >> Trying to set the timing.
> >>
> >> Can't do it.
> >>
> >> Engine starts easily and runs, but very ragged.
> >>
> >> Intermittent no spark to each plug. Will show a spark correctly for 1
> >> or 2 or 5 or whatever correct rotations; then go away for various
> >> periods from momentary to up to several seconds; then more of the
> >> same. Apparent at idle and at higher rpm's -- with the only
> >> difference in the rate of spark obviously correlated with engine
> >> speed.
> >>
> >> Can be observed by putting the inductive timing light sensor on #1; or
> >> any other cylinder wire; or on the coil-to-distributor wires.
> >>
> >> Got a second inductive timing light. Same exact symptoms. (Both
> >> timing lights work just fine on my 90 Cherokee).
> >>
> >> Battery is good and fully charged. Weather is warm (I live in
> >> Florida). Have replaced the coil, the distributor cap & rotor, the
> >> plugs, and the plug wires. Nothing made any difference.
> >>
> >> No evidence of any corrosion or other obvious mechanical issues inside
> >> the distributor or elsewhere.
> >>
> >> Have owned the vehicle since new so I know there have been no
> >> modifications to the electrical system.
> >>
> >> Help please -- what do I check now. What should I do??
> >>
> >> Thanks ......
> >>
> >> Mike
> >> Michael Pomeroy
>
> Michael Pomeroy

 

A bad ground comes to mind next, then a bad ignition module.

I test the grounds with a booster cable. I run it from the battery
negative to the engine block and see what happens, if the same I then
tag the distributor itself with the booster cable. (I have seen a few
distributors loose their ground due to surface rust)

If still no joy I then tag the firewall with the booster cable and then
the ignition module itself. The module needs a good ground or it will
try and steal one through the distributor.

How is the fuel filter? A plugged up one can starve the carb for fuel
at idle and cause the inductive miss you see. When the pump comes up in
speed, it can force gas through a partially plugged filter.

So can a fuel filter that is in upside down. If upside down, it will
pump too much gas back to the tank at idle and can starve the carb for
fuel.

Just a few more thoughts for you...

Mike

pomerom@yahoo.com wrote:
>
> Mike,
>
> Didn't say this in the initial posting because I didn't think it
> relevant, but original carb is gone and there is a Weber on there now.
>
> And I don't know for sure, but looking back and thinking back I
> believe I've had this problem for some time -- even when the original
> carburator was still in place. (The Scrambler is driven on an
> irregular basis.)
>
> Still no joy -- more suggestions please ......
>
> Mike
>
> On Thu, 15 Jan 2004 09:44:58 -0500, Mike Romain <romainm@sympatico.ca>
> wrote:
>
> >I got suckered with those symptoms and an inductive timing light and
> >went after parts.
> >
> >It was plugged idle tubes in the carb. The lack of or wrong amount of
> >gas reaching the plugs affected the timing light implying a spark
> >problem.
> >
> >I figured it out after there was nothing electrical left to change...
> >
> >Here is a link on the idle tubes and the fix for them. I can fix them
> >from the top in about 15 minutes now that I know how to do it.
> >
> >http://www.off-road.com/jeep/tech/engine/carter.html
> >
> >Also a kit for that carb is only twenty bucks or so and should be done
> >with every major tuneup or spark plug change.
> >
> >Mike
> >86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> >88 Cherokee 235 BFG AT's
> >
> >pomerom@yahoo.com wrote:
> >>
> >> Trying to set the timing.
> >>
> >> Can't do it.
> >>
> >> Engine starts easily and runs, but very ragged.
> >>
> >> Intermittent no spark to each plug. Will show a spark correctly for 1
> >> or 2 or 5 or whatever correct rotations; then go away for various
> >> periods from momentary to up to several seconds; then more of the
> >> same. Apparent at idle and at higher rpm's -- with the only
> >> difference in the rate of spark obviously correlated with engine
> >> speed.
> >>
> >> Can be observed by putting the inductive timing light sensor on #1; or
> >> any other cylinder wire; or on the coil-to-distributor wires.
> >>
> >> Got a second inductive timing light. Same exact symptoms. (Both
> >> timing lights work just fine on my 90 Cherokee).
> >>
> >> Battery is good and fully charged. Weather is warm (I live in
> >> Florida). Have replaced the coil, the distributor cap & rotor, the
> >> plugs, and the plug wires. Nothing made any difference.
> >>
> >> No evidence of any corrosion or other obvious mechanical issues inside
> >> the distributor or elsewhere.
> >>
> >> Have owned the vehicle since new so I know there have been no
> >> modifications to the electrical system.
> >>
> >> Help please -- what do I check now. What should I do??
> >>
> >> Thanks ......
> >>
> >> Mike
> >> Michael Pomeroy
>
> Michael Pomeroy

 

A bad ground comes to mind next, then a bad ignition module.

I test the grounds with a booster cable. I run it from the battery
negative to the engine block and see what happens, if the same I then
tag the distributor itself with the booster cable. (I have seen a few
distributors loose their ground due to surface rust)

If still no joy I then tag the firewall with the booster cable and then
the ignition module itself. The module needs a good ground or it will
try and steal one through the distributor.

How is the fuel filter? A plugged up one can starve the carb for fuel
at idle and cause the inductive miss you see. When the pump comes up in
speed, it can force gas through a partially plugged filter.

So can a fuel filter that is in upside down. If upside down, it will
pump too much gas back to the tank at idle and can starve the carb for
fuel.

Just a few more thoughts for you...

Mike

pomerom@yahoo.com wrote:
>
> Mike,
>
> Didn't say this in the initial posting because I didn't think it
> relevant, but original carb is gone and there is a Weber on there now.
>
> And I don't know for sure, but looking back and thinking back I
> believe I've had this problem for some time -- even when the original
> carburator was still in place. (The Scrambler is driven on an
> irregular basis.)
>
> Still no joy -- more suggestions please ......
>
> Mike
>
> On Thu, 15 Jan 2004 09:44:58 -0500, Mike Romain <romainm@sympatico.ca>
> wrote:
>
> >I got suckered with those symptoms and an inductive timing light and
> >went after parts.
> >
> >It was plugged idle tubes in the carb. The lack of or wrong amount of
> >gas reaching the plugs affected the timing light implying a spark
> >problem.
> >
> >I figured it out after there was nothing electrical left to change...
> >
> >Here is a link on the idle tubes and the fix for them. I can fix them
> >from the top in about 15 minutes now that I know how to do it.
> >
> >http://www.off-road.com/jeep/tech/engine/carter.html
> >
> >Also a kit for that carb is only twenty bucks or so and should be done
> >with every major tuneup or spark plug change.
> >
> >Mike
> >86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> >88 Cherokee 235 BFG AT's
> >
> >pomerom@yahoo.com wrote:
> >>
> >> Trying to set the timing.
> >>
> >> Can't do it.
> >>
> >> Engine starts easily and runs, but very ragged.
> >>
> >> Intermittent no spark to each plug. Will show a spark correctly for 1
> >> or 2 or 5 or whatever correct rotations; then go away for various
> >> periods from momentary to up to several seconds; then more of the
> >> same. Apparent at idle and at higher rpm's -- with the only
> >> difference in the rate of spark obviously correlated with engine
> >> speed.
> >>
> >> Can be observed by putting the inductive timing light sensor on #1; or
> >> any other cylinder wire; or on the coil-to-distributor wires.
> >>
> >> Got a second inductive timing light. Same exact symptoms. (Both
> >> timing lights work just fine on my 90 Cherokee).
> >>
> >> Battery is good and fully charged. Weather is warm (I live in
> >> Florida). Have replaced the coil, the distributor cap & rotor, the
> >> plugs, and the plug wires. Nothing made any difference.
> >>
> >> No evidence of any corrosion or other obvious mechanical issues inside
> >> the distributor or elsewhere.
> >>
> >> Have owned the vehicle since new so I know there have been no
> >> modifications to the electrical system.
> >>
> >> Help please -- what do I check now. What should I do??
> >>
> >> Thanks ......
> >>
> >> Mike
> >> Michael Pomeroy
>
> Michael Pomeroy

 

Some stores, NAPA, maybe others will also test the module for you. BUT
the test is not always conclusive. I had a bad module that tested fine
on the machine but had just left me stranded. Your problem sounds alot
like what was happening when mine went bad. Would be driving down the
road then the motor would just start missing. One thing I was told was
to watch your tach, if you have one, if it is dropping to zero, while
the motor is missing then it is you module.


In article <HrL6L9.9C8@news.boeing.com>,
"breyfogle" <breyfogle@aol.com> wrote:

> I have had more than one fail with NO external sign of anything wrong.
> Swapping modules is the only real way of checking for a bad ignition module.
> <pomerom@yahoo.com> wrote in message
> news:uume00l7o9ivdnu9vkgudm61im70p048bd@4ax.com...
> > Thanks for the suggestion.
> >
> > I inspected it closely. No obvious sign of any problem.
> >
> > So still stumped ......
> >
> > Mike
> >
> > On 15 Jan 2004 05:05:34 GMT, onlyinajeepcj7@aol.com (Onlyinajeepcj7)
> > wrote:
> >
> > >also check the ign box (drivers inner fender under water bottle) if back
> is
> > >melted, it is bad or on it's way out.
> >
> > Michael Pomeroy
>
>

--
o_o_o_o
/| ,[_____],
|ŻŻŻL --O|||||||O-
()_)Ż()_) ŻŻŻŻŻ )_)

 

Some stores, NAPA, maybe others will also test the module for you. BUT
the test is not always conclusive. I had a bad module that tested fine
on the machine but had just left me stranded. Your problem sounds alot
like what was happening when mine went bad. Would be driving down the
road then the motor would just start missing. One thing I was told was
to watch your tach, if you have one, if it is dropping to zero, while
the motor is missing then it is you module.


In article <HrL6L9.9C8@news.boeing.com>,
"breyfogle" <breyfogle@aol.com> wrote:

> I have had more than one fail with NO external sign of anything wrong.
> Swapping modules is the only real way of checking for a bad ignition module.
> <pomerom@yahoo.com> wrote in message
> news:uume00l7o9ivdnu9vkgudm61im70p048bd@4ax.com...
> > Thanks for the suggestion.
> >
> > I inspected it closely. No obvious sign of any problem.
> >
> > So still stumped ......
> >
> > Mike
> >
> > On 15 Jan 2004 05:05:34 GMT, onlyinajeepcj7@aol.com (Onlyinajeepcj7)
> > wrote:
> >
> > >also check the ign box (drivers inner fender under water bottle) if back
> is
> > >melted, it is bad or on it's way out.
> >
> > Michael Pomeroy
>
>

--
o_o_o_o
/| ,[_____],
|ŻŻŻL --O|||||||O-
()_)Ż()_) ŻŻŻŻŻ )_)

 

Some stores, NAPA, maybe others will also test the module for you. BUT
the test is not always conclusive. I had a bad module that tested fine
on the machine but had just left me stranded. Your problem sounds alot
like what was happening when mine went bad. Would be driving down the
road then the motor would just start missing. One thing I was told was
to watch your tach, if you have one, if it is dropping to zero, while
the motor is missing then it is you module.


In article <HrL6L9.9C8@news.boeing.com>,
"breyfogle" <breyfogle@aol.com> wrote:

> I have had more than one fail with NO external sign of anything wrong.
> Swapping modules is the only real way of checking for a bad ignition module.
> <pomerom@yahoo.com> wrote in message
> news:uume00l7o9ivdnu9vkgudm61im70p048bd@4ax.com...
> > Thanks for the suggestion.
> >
> > I inspected it closely. No obvious sign of any problem.
> >
> > So still stumped ......
> >
> > Mike
> >
> > On 15 Jan 2004 05:05:34 GMT, onlyinajeepcj7@aol.com (Onlyinajeepcj7)
> > wrote:
> >
> > >also check the ign box (drivers inner fender under water bottle) if back
> is
> > >melted, it is bad or on it's way out.
> >
> > Michael Pomeroy
>
>

--
o_o_o_o
/| ,[_____],
|ŻŻŻL --O|||||||O-
()_)Ż()_) ŻŻŻŻŻ )_)

 

Have you checked the voltage at the coil? If your `82 is the same as my
`79, the coil gets full battery voltage while cranking from a terminal on
the starter relay, then drops to a lower voltage (via a resistive link
spliced into the harness) while running. If there's a corroded splice or
terminal in the "run" circuit someplace, you'll get easy starts (full
voltage) but crappy running (low or intermittant voltage).

Just a thought.


On Thu, 15 Jan 2004 pomerom@yahoo.com wrote:

> Trying to set the timing.
>
> Can't do it.
>
> Engine starts easily and runs, but very ragged.
>
> Intermittent no spark to each plug. Will show a spark correctly for 1
> or 2 or 5 or whatever correct rotations; then go away for various
> periods from momentary to up to several seconds; then more of the
> same. Apparent at idle and at higher rpm's -- with the only
> difference in the rate of spark obviously correlated with engine
> speed.
>
> Can be observed by putting the inductive timing light sensor on #1; or
> any other cylinder wire; or on the coil-to-distributor wires.
>
> Got a second inductive timing light. Same exact symptoms. (Both
> timing lights work just fine on my 90 Cherokee).
>
> Battery is good and fully charged. Weather is warm (I live in
> Florida). Have replaced the coil, the distributor cap & rotor, the
> plugs, and the plug wires. Nothing made any difference.
>
> No evidence of any corrosion or other obvious mechanical issues inside
> the distributor or elsewhere.
>
> Have owned the vehicle since new so I know there have been no
> modifications to the electrical system.
>
> Help please -- what do I check now. What should I do??
>
> Thanks ......
>
> Mike
> Michael Pomeroy
>

 

Have you checked the voltage at the coil? If your `82 is the same as my
`79, the coil gets full battery voltage while cranking from a terminal on
the starter relay, then drops to a lower voltage (via a resistive link
spliced into the harness) while running. If there's a corroded splice or
terminal in the "run" circuit someplace, you'll get easy starts (full
voltage) but crappy running (low or intermittant voltage).

Just a thought.


On Thu, 15 Jan 2004 pomerom@yahoo.com wrote:

> Trying to set the timing.
>
> Can't do it.
>
> Engine starts easily and runs, but very ragged.
>
> Intermittent no spark to each plug. Will show a spark correctly for 1
> or 2 or 5 or whatever correct rotations; then go away for various
> periods from momentary to up to several seconds; then more of the
> same. Apparent at idle and at higher rpm's -- with the only
> difference in the rate of spark obviously correlated with engine
> speed.
>
> Can be observed by putting the inductive timing light sensor on #1; or
> any other cylinder wire; or on the coil-to-distributor wires.
>
> Got a second inductive timing light. Same exact symptoms. (Both
> timing lights work just fine on my 90 Cherokee).
>
> Battery is good and fully charged. Weather is warm (I live in
> Florida). Have replaced the coil, the distributor cap & rotor, the
> plugs, and the plug wires. Nothing made any difference.
>
> No evidence of any corrosion or other obvious mechanical issues inside
> the distributor or elsewhere.
>
> Have owned the vehicle since new so I know there have been no
> modifications to the electrical system.
>
> Help please -- what do I check now. What should I do??
>
> Thanks ......
>
> Mike
> Michael Pomeroy
>

 

Have you checked the voltage at the coil? If your `82 is the same as my
`79, the coil gets full battery voltage while cranking from a terminal on
the starter relay, then drops to a lower voltage (via a resistive link
spliced into the harness) while running. If there's a corroded splice or
terminal in the "run" circuit someplace, you'll get easy starts (full
voltage) but crappy running (low or intermittant voltage).

Just a thought.


On Thu, 15 Jan 2004 pomerom@yahoo.com wrote:

> Trying to set the timing.
>
> Can't do it.
>
> Engine starts easily and runs, but very ragged.
>
> Intermittent no spark to each plug. Will show a spark correctly for 1
> or 2 or 5 or whatever correct rotations; then go away for various
> periods from momentary to up to several seconds; then more of the
> same. Apparent at idle and at higher rpm's -- with the only
> difference in the rate of spark obviously correlated with engine
> speed.
>
> Can be observed by putting the inductive timing light sensor on #1; or
> any other cylinder wire; or on the coil-to-distributor wires.
>
> Got a second inductive timing light. Same exact symptoms. (Both
> timing lights work just fine on my 90 Cherokee).
>
> Battery is good and fully charged. Weather is warm (I live in
> Florida). Have replaced the coil, the distributor cap & rotor, the
> plugs, and the plug wires. Nothing made any difference.
>
> No evidence of any corrosion or other obvious mechanical issues inside
> the distributor or elsewhere.
>
> Have owned the vehicle since new so I know there have been no
> modifications to the electrical system.
>
> Help please -- what do I check now. What should I do??
>
> Thanks ......
>
> Mike
> Michael Pomeroy
>