H.O/XJ Tech. 4.0 Shutting off while driving.

[Kenosha Warrior]

1995 XJ. 4.0 AW4, the usual outfit for a 4dr XJ.

 

Has 'moments' as the woman likes to call them. As you're driving (any speed/rpm. Issue is not dependent on these two factors) it will lose RPM momentarily, bounce back and then die. No sputter as if losing fuel, seems to be more of an ign problem. I've replaced the coil dizzy/cap and rotor assembly when I first diagnosed a short to ground within the distributor. MOST times it will require a few minutes to sit, as cranking it over results in nothing. Sometimes I smell unburnt fuel out the tailpipe and sometimes I do not. The CPS is less than a year old.

 

Anyone experienced anything like this? It does it about once a week, with about 4-5 days between 'moments' I have recently found that unplugging the TPS, it will fire up and then I plug it back in to continue my rudely interrupted journey.

 

*edit* The fuel pump is brand new, about a month old. Maintains pressure, ect.

[87Warrior]

Sure sounds like it could be the CPS. My folks 93 XJ was doing the same thing while I was driving it for a month. Replaced the CPS with a Mopar unit and it hasn't done it again. That was 1 year ago.

 

Maybe you could try a new TPS. You even mentioned that it (or removal) helped get it running again..

 

Can you pull the codes with the 3 on key trick? Even if the CEL is not illuminated it could be storing codes. Or is the 95 OBDii?

[HOrnbrod]

I agree it could be the CPS, Camshaft Position sensor in the distributor. Also called a hall effect sensor or pick-up coil. I had one fail in a 95XJ I had causing the same symptoms. It was toast and misfired causing the fuel system to shut down sporadically. Can't test it, can only be replaced. Also check the codes as mentioned before. Look for a code 11.

[JeepcoMJ]

The crank sensor would cause this issue if you didn't tie it up properly and it is contacting the exhaust manifold