So I've been working on trying to diagnose and fix the issues with my jeep for a couple of weeks now. I was driving the car home after a long day of driving it around (about 5 hours of doing deliveries with it), and while at speed (35ish) the engine cut off, taking power steering and brakes with it. I was able to come to a stop, and get it started again to travel a bit farther. This happened two more times, and the final time it simply wouldn't turn over. It will crank, and after resting it will seem to just barely start, then shudder and cut out, then go back to only cranking. Since then I've been in diagnostics hell trying to get poor Thaddeus back on the road.

The things I have so far replaced are (in order):

• Battery (needed replacement soon anyway)
• Fuel Pump
• Fuel Filter (definitely still glad to have replaced this)
• Spark Plugs (not sure how it was even running before with the state of these)
• Camshaft sensor
• Crankshaft sensor
• Powertrain Control Module

I do have an oil leak on the right cylinder head cover (a small crack), the leak has been a known issue for a while, and discovered the crack while working on this diagnosis, no idea if it's related or not.

I've tested every fuse, and relay I could get my hands on, and none of them seem to be an issue. I've been pouring over schematics and electrical diagrams trying to diagnose what could even cause this.

From what I've gathered so far, the PCM isn't grounding the ASD relay, so there is no power going to the Injectors, Coils or the O2 sensor. I've tried jumping the ASD relay, and all that does it cause one of the O2 sensors to click (I'm pretty sure that's what's doing it), but still no start).
I know that it's getting fuel into the rail, there's no short between the ASD relay and the injectors, plugs, or sensors, or between the PCM and the ASD.

I'm currently at wits end, and banging my head against the wall, so any help or ideas of what to test next would be amazing.


Thank you