Mattloz

Ok so I had no luck in the oem section with this issue so here we go again

I own a 1990 jeep Cherokee I have a no crank no start issue I followed cruisers54 tips for this issue the cps was shot and bought a new one and it works correctly but no spark, so I bought a new coil and still no spark, I doubled check all my grounds and wiring and all seems good used a 4g wire from the fire wall to a intake/exhaust bolt ( replaced the ground strap)

After a little research I tried to see if I was getting a signal to the icm/icu and nothing I just bought a new icm/icu to see if that's the case my last resort after that is a distributor pick up

Any ideas guys help please

Mattloz

hey guys i just changed mt icm ( ignition control module) and i still get no spark at all i checked for injector pulse and i get nothing also what the heck is going on i need help please

Lancethedance

Don't know if not enough cold cranking amps on the battery would not give you a spark but I thought I'd mention it.

Lancethedance

Have you tried jumping the solenoid on the starter?

F1Addict

Is it "crank no start" as the thread title suggests or "no crank no start" as you stated in your request? I suspect it's the former and, if that is the case, it sounds like an ECU issue. I recall reading (years ago) of a way to test the ECU for proper handling of the CPS signal but it's been a really long time. I believe in the case I am remembering, the ECU had failed. Perhaps Cruiser, our resident Renix savant will stumble upon this and offer his sage advice. He is your best hope.

Mattloz

Sorry I had a crank no start issue ( misspelled) I have no spark but engine does turn over I changed the cps ignition and other things, well I removed the ecu and we'll I found my problem I saw a burned wire ( the cooper lines in the mother board) well today my manager ( I'm a gym service technician ) and my manager know how to soder, he's hoing to try to bypass it and see what happens

I do have another question when I turn the ignition on ( not starting) I use to hear the fuel pump prime( when I was draining about .5gal of gas to get old gas out of the tank) , now after I did that I had connected everything and tried to start the engine for the first time but now I don't hear it prime, when I start to crank the Engine over the fuel pump pushes fuel through the rail is that normal or should it prim everytime I cycle the ignition?

Also I send cruisers a private message I believe he replied I'll check now

F1Addict

If there is sufficient pressure in the lines, the fuel pump won't prime.

Burnt traces in the ECU are rare. In fact, I've never heard of this happening. Happens all the time with the wiper control module but not the ECU. Fortunately, Renix ECUs can be found for pretty cheap (~$50) in case your boss's soldering skills aren't all he/she claims them to be.

Mattloz

Wow really on eBay they range from like 80-100 but there is s member here willing to sell one that he has for 50 plus shipping ( most likely will take offer) and I'm also messaging cruiser he has earlier renix ecu which produce little less power but I think sufficient enough