Cranks but won't start- Figured it out

My 1996 xj would not start. It cranked but would not ever run. I had a long post last week and finally figured it out.
I replaced ignition, CPS, and Coil but still had no spark.

Search under " Cranks but won't fire, Neutral safety switch?" for the whole progression.

I think the key thing was that when it would not start I would turn on the key and the electric fan was running.

But a friend turned me on to the PCM (computer) wiring. Today the jeep just stopped on me so I started trying a few things. But it would not start. Finally I checked the PCM wiring and one of the plug ins has a broken plastic tab on it. This allowed it to wiggle a little loose and not have full contact. Once I pushed it in a little the jeep started right up.

See the electric fan running should have been a clue that the PCM was malfunctioning. The electric fan should not run until the temp sensor tells the computer that the motor is hot or the AC tells the computer that it is on. The plug on the PCM must have made it read a few things wrong.

So what did I learn- try the cheap and easy stuff first.
Thanks to every one for their help!

You could have multiple problem, bad fuel pump to name one. May be money ahead to tow it to a garage, have them check it over use the test set. That will be cheaper than throwing parts at it.. also if you have an AAA or other autoclub membership the tow should be free.

Time for some "professional help".

No spark is normally indicative of a bad CPS. You said you swapped the CPS, so the next thing to do is to unplug the computer and then replug it back in. A bad contact on the computer can cause this as well.

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I guess you read the responses. Sure feels good to have it running again, doesn't it.