Engine just quit

2001 XJ, 4.0, AW4, np231, 218,xxx miles. Engine, trans and transfer case are original and stock. Jeep started normally and I let it warm up for a few minutes at idle before driving. About 3 minutes into my drive the next traffic light turned yellow and I lifted off the gas and let it coast in drive to the light. As I applied the brakes and almost to a complete stop I noticed the rpms were at zero. I put it in neutral and tried to restart and it cranked but no start. Everything electrical was still working cause the radio was still on. I pushed it to the side of the road and put it in park and shut the key off. Waited a minute and it fired right up. Drove it for another 10 minutes and had no issues. When it died it didn't stutter or stumble, it just shut off. Any ideas?

My 87 just did this too.
I have a new cps, among a ton of new engine sensors and tune up parts. Very odd

Sounds like a bad CPS

Will a bad cps trip the cel?

Ian Christiansen said:

Will a bad cps trip the cel?

Click to expand...

Yes.

jeepdreamer said:

Yes.

Click to expand...

Not always

Identical symptoms we experienced earlier this year, thought it might have been a malfunctioning fuel pump. Pressure testing ruled that out. No codes were present.

We swapped out the ASD and fuel pump relays, and tightened up all plug connections in the box. It has run perfectly since.

Crankshaft position sensor and not camshaft position sensor I assume. I will be pulling the cel codes tonight after work.

Ian Christiansen said:

Crankshaft position sensor and not camshaft position sensor I assume. I will be pulling the cel codes tonight after work.

Click to expand...

As sidewaysstarion said, a bad CPS won't always trigger a CEL or register a code. I had a bad misfire that never triggered a code and a new CPS fixed it.

Remember - chain auto parts store CPS are crap. The best come from the dealer. Second choice would be NAPA.

I've had bad crankshaft position sensors short to ground... Which prevented the ecu from even booting properly... The odb2 reader wouldn't even connect. Codes aren't a mechanic.

any of the engine sensors can do this.

Last time our 01 shut off it was the oil pressure sender.
unplugged it and the no bus went away and it ran quite normally.

Changed the cps with a Napa one. Started up and drove home with no issues. It died on me this morning once and then after work I couldn't keep it running. When I first started it this afternoon it ran for a few minutes and shut off. Everytime I'd restart it, it would seen to run for less time. Got to the point it would only run for 5-10 seconds. After the change it started right up and I let it run for about 15 minutes at idle and then drove home from work which is about 15 minutes. Hopefully that fixed it. Never changed one of those before and I never want to do it again. Thanks for everyones help.