B.RAIDER
NAXJA Forum User
- Location
- Central Texas
1988 Jeep Cherokee 4.0, I6, Auto Trans, 4X4
Trying to diagnose a no start problem.
All grounds are good and battery is strong.......
At times the Jeep will start and run fine for about 5 mins or so then shut down.
After a bit it will restart.....sometimes 10 to 15 mins....sometimes not for hours.
I have determined that it is not a fuel problem by testing the fuel pressure with a gauge at the fuel rail. Also Have new fuel filter installed.
Also the CPS at the flywheel is new. It also checks out good by ohming it (222 ohms).
When it shuts off …… I have no spark from the coil.
I do have power at the ignition wire(12 volts) to the three wire ignition module plug….but no tach signal from the module plug when cranking (I checked these by probing while plug is connected).
I have also checked the pin at the D1 diagnostic connector….no tach signal there either when cranking.
Does this indicate that the ignition control module under the coil is bad?
Or could it be something else?
Is there something else I should check in conjunction with what I have checked so far?
There are a brazillion threads on this topic have read a bunch of em but have not yet found my answer.
Thanks ahead of time for any help................
Trying to diagnose a no start problem.
All grounds are good and battery is strong.......
At times the Jeep will start and run fine for about 5 mins or so then shut down.
After a bit it will restart.....sometimes 10 to 15 mins....sometimes not for hours.
I have determined that it is not a fuel problem by testing the fuel pressure with a gauge at the fuel rail. Also Have new fuel filter installed.
Also the CPS at the flywheel is new. It also checks out good by ohming it (222 ohms).
When it shuts off …… I have no spark from the coil.
I do have power at the ignition wire(12 volts) to the three wire ignition module plug….but no tach signal from the module plug when cranking (I checked these by probing while plug is connected).
I have also checked the pin at the D1 diagnostic connector….no tach signal there either when cranking.
Does this indicate that the ignition control module under the coil is bad?
Or could it be something else?
Is there something else I should check in conjunction with what I have checked so far?
There are a brazillion threads on this topic have read a bunch of em but have not yet found my answer.
Thanks ahead of time for any help................
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