Evan Waring

I have a 1995 Cherokee with an inline 6. We changed the crank sensor, o2 sensor, coil pack, camshaft sensor, just about everything we could change. It doesnt get any spark whatsoever. There might be a thread for this somewhere but I couldn't find it. Thanks in advance for the help

PatHenry

ASD relay?

Did you use a Mopar CPS?

Evan Waring

I havent checked the relays, I pulled the computer out and looked at it. I used standard t-series cps

tjwalker

Spark: 12 volts from ignition switch to the ASD relay; when the key is first turned on the PCM provides a ground to the ASD relay to energize it, then the ASD relay passes 12 volts to the coil primary side. If no crank sensor signal is generated after a couple of seconds the PCM cuts the ground to the ASD relay (and fuel pump relay too) and that cuts power to the coil (and fuel pump). Key to START and once again the PCM energizes the ASD relay. Now, a critical element is the crank sensor--no signal from the crank sensor and the PCM won't trigger the coil to provide spark.