no13

Hi all, I'm a lurker and have posted once or twice. I have a question.

Recently, I've narrowed down a cold starting problem to my computer.

I'm on the hunt for a used one and the past few weeks have turned up various answers.

One source says the computer from a 91 with the 4.0 w/manual trans MUST be replaced with one from ONLY a 91 with the 4.0 w/manual trans

Other sources say a 91-95 will work

Yet other sources say it has to be programmed... while others say its a plug-n-play item.

I'm not opposed to getting a replacement... but I'm unsure what to do here. Seems nobody has the same answer.

Can anyone here, without question, tell me what computer will work?

Thanks for your time.

tjwalker

I can't help you with the compatibility, but I will tell you that computers are blamed far more frequently than they are the root cause.

A problem with cold starting is not typically a computer problem. Can you tell us why you think that is the cause? Just curious.....

no13

You bet:
1. Fuel pump does not prime when cold, will crank over just fine. Evenutally, after a while, the pump will turn on and it will start, runs weird but after a sec runs fine. Never has the problem when warm. Pump is new, tested 3 different pumps, I now have a nifty access hatch to get at the pump.
2. All wiring good, tested myself
3. battery new, all cables new, starter (both old & new) good.
4. Fuel pump relays good, new, all checks out.
5. If I leave the key in the ON pos, eventually, you'll hear a slight (really slight) high pitch noise coming from the computer, then eventually, you'll hear the relay start clicking... then it engages.

6. On a whim (knowing it always works when warm), I took a space heater outside put it face down on top of the computer for 15 min... starts right up after that.

Computer problem.

I mean, I love my heater solution, but it gets old.