No start no spark now what?

[jeffc80444]

I have no spark from the coil wire (brand new) to the terminal on the cap. I'm not sure where the wires that plug into the coil come from but I have no power with the switch on to either of the two. I don't know where to go from there.

[Mudderoy]

Several things, but I'll name a few people can add or correct me. :D

Bad CPS (Crank Position Sensor)
Bad NSS (I don't think it will even turn over when this is bad though)
Bad speed sensor
Bad ECM (computer or connection to it)

[cpttuna]

When the NSS is not working, the engine will not crank. Try and loosen the nss and wiggle it a little.

[jeffc80444]

hmmm, sounds like it's time to enlist the services of a pro mechanic.

[denverd1]

What was done since it ran last?

[sidewaysstarion]

What year is it?

[slvmart]

Jeff's info shows it as a 1991, so that should be the Chrysler (non-Renix) version.

[sidewaysstarion]

Jeff's info shows it as a 1991, so that should be the Chrysler (non-Renix) version.

Ahh ok, that's the first year of SBEC (PCM family). I have a guy here locally with a 92 that has a similar issue. I hooked my DRB up to it and made sure it was seeing a signal from the CKPS and the CPS. I ran a coil test and it wouldn't produce a spark. I checked wiring and the coil itself. We tried another ECM and it fired right up.

Since your jeep is a 91 you can rule out a bad NSS and VSS.

What I would do is replace the CPS which is the most common failure point and if that doesn't fix it I would find a 91-95 PCM to see if it will start with a spare PCM.