Engine Keeps Killing. Starts when i reset the battry.

RIG: 91' automatic 4wd xj with a 96' 4.0 HO but still obd 1

SYMPTOMS: When I was driving the engine just killed. The battery, temp, oil pressure gauges are all good. It wont fire up again unless I dis/re-connect the battery. Then it starts fine, but wont run more than a minute or so.

A LITTLE MORE BACKGROUND: I rolled my jeep coming down a trail two days ago. I had to replace the radiator. I think some sensor may have jolted loose and gotten looser over the following 24 hrs as I drove it (it's my daily driver).

PROB: It's a complete mystery to me really, haha. So thanks for your help in advance!

-Andrew

Ask yourself what will kill a motor. No spark, no fuel, no air. Not so often, way too much fuel or a plugged exhaust. Have you looked at your air cleaner?

First thing I'd do is is pull the relays and plug them back in again, make sure they are seated. Fuses will sometimes act like a bi metal, they open when they get hot. Look really close at the fuses, use the end of your finger to find the hot one.
Do a key test and see what MIL codes pop up.
Could be any number of electrical connections, start with the easy ones.

Coolant is a conductor, it will really screw with your electronics. The best way to clean it off is really hot water, almost boiling is the best.

Twice I've popped a hole in a radiator and had it spew, both times it cost me an alternator.

I'd say it is reading a sensor wrong or a bad sensor. When you reset the PCM it clears out the learned info from the sensors. It then can learn bad habbits from faulty sensor data. I would start by testing the CTS, MAP and CPS.

Also check the harness and make sure it didn't shift during the roll over and is now touching the exhaust or is rubbing on something causing a short.

I ran a test with obd1, cps problem. that made sense. but idk if it's a bad sensor, or if the sensor is picking up something that it ought to.
Also, I was washing my car yesterday and had to reset the battery to start it up again. The jeep hasnt killed in the last three days of driving it.

Does this help at all?

So, it ran fine for 3 days then you washed it and it wouldn't start and you had to disconnect the battery?

Talyn said:

So, it ran fine for 3 days then you washed it and it wouldn't start and you had to disconnect the battery?

Click to expand...

Exactly. As soon as I connected it it started fine

Hrm.. I would look for a bad connector or frayed wire. Check around any moving part like the axle shafts. Check any wire that is close to anything, particularly behind the valve cover.