1988JeepXj
NAXJA Forum User
- Location
- Redford, Mi
Okay, bear with me on this one. My buddy's '92 Laredo 4.0 a/t has been acting up pretty good as of late. Problem originated as a really bad misfire under a light load, no codes. Anyway, one day on his way home from work it dies at a light, and all it does is start/stall. So he panics, starts it up revs it to the moon and slams it into gear, bang. Drives fine after that EXCEPT, now it misfires only when making left hand turns...?
That brings us to yesterday. He calls me up, Jeep died just driving down the road, just cut out, nothing. So I go check it out, break out the Power Probe, Maxi-fuse 15 (engine management, 30a) in the PDC is blown. Give it power with the probe, starts right up, cool. Throw a new fuse in it it runs again, he goes to leave and the second he hits the gas leaving the driveway, dead. Same fuse blown. Throw one last fuse in it thinking maybe with any luck the last one was defective, no luck. Fires it up, and the second he throws it in drive, didn't even get a chance to take his foot off the brake, dead again. Obviously something is shorting out.
The strange part is, if you make it run and its just sitting there, you can shake, tug on, yank any wire or plug in the engine compartment including the wires near the PDC and nothing happens. You can rev it all you want, nothing, it runs fine when its not moving.
Now for my question(s), I noticed in the wiring diagram that the same fuse that keeps going bad also powers the TCU. I have to believe the problem is somewhere in the splice from the engine compartment to the TCU, since all the engine compartment wires seem okay. Is there a particular connector or wire chaffing point I should look for? I know some '94/'95s had a chaffing problem under the left kick panel somewhere, but that was related to power windows/locks. Could it be possible that the trans controller is shorting out internally?
I haven't had a chance to toy with it much other than towing him home yesterday.
TIA
That brings us to yesterday. He calls me up, Jeep died just driving down the road, just cut out, nothing. So I go check it out, break out the Power Probe, Maxi-fuse 15 (engine management, 30a) in the PDC is blown. Give it power with the probe, starts right up, cool. Throw a new fuse in it it runs again, he goes to leave and the second he hits the gas leaving the driveway, dead. Same fuse blown. Throw one last fuse in it thinking maybe with any luck the last one was defective, no luck. Fires it up, and the second he throws it in drive, didn't even get a chance to take his foot off the brake, dead again. Obviously something is shorting out.
The strange part is, if you make it run and its just sitting there, you can shake, tug on, yank any wire or plug in the engine compartment including the wires near the PDC and nothing happens. You can rev it all you want, nothing, it runs fine when its not moving.
Now for my question(s), I noticed in the wiring diagram that the same fuse that keeps going bad also powers the TCU. I have to believe the problem is somewhere in the splice from the engine compartment to the TCU, since all the engine compartment wires seem okay. Is there a particular connector or wire chaffing point I should look for? I know some '94/'95s had a chaffing problem under the left kick panel somewhere, but that was related to power windows/locks. Could it be possible that the trans controller is shorting out internally?
I haven't had a chance to toy with it much other than towing him home yesterday.
TIA