OK so im a LRF member and im normally on talking disco. but i am helping a friend of mine at work with his 1990 wrangler yj 4.2. apparently it has sat up for a few years without moving. when you go to turn it over there is no spark! power is making it to the distributor but is not moving past it into the rest of the ignition system. things that were done by our other friend when he looked at are. dizzy cap,rotor, plugs,wires and ignition coil, fuel pump fuel filter. that only leaves the relay,switch, pick up coil, and ignition control module.

any hints on trying to help me narrow this down? id love to help him fix this jeep so we can wheel the yj vs the disco 1.

fyi fuses checked as well. battery on trickle charger, starter good, motor turns but no burning of fuel. got air, got fuel, NO SPARK.

thanks in advance yall.

steven/walko327

 

Do they have crank position sensors. Locate it and either replace it or test it.

Search around the bell housing area for it, if it exists on that motor.

 

Hang a meter across the ignition coil primary wires when trying to start it. You should see some change in the voltage on it. If so, then it's the coil, if not, it's the ignition module. I'm betting it's the module.

 

Bad ignition module.

 

thanks guys for the hand in this abomination. It does have a crank sensor and I thought maybe it too. but I was leaning most towards the ICm. Though I will test these things as well, heading that way this weekend.

Again thanks for the help the wrangler forum members seem to just like throwing cheap heep parts at their trucks, and not diagnosing the first time. I guess when all your parts are cheap chinese and cheap chrysler parts you can afford to switch everything out.

Steven

 

And thats what separates Rover people from Jeep people, they like cheap quick, easy and no brains required repairs, Rover people like a challenge.

 

I had a 2000 Cherokee with a straight 6 do the same thing, and yes it was the crank sensor.