OBD 1 problem,94 Chereokee

[70 beater]

I need help with a '94 Cherokee.This thing will just stop running,may or may not restart.No warning,just like key gets switched off,runs fine otherwise.Not a fuel issue.I can start throwing parts at it,and probably get it,but I'd rather not do that.Going to pull the coil and test,or have it tested.Also have to replace the oil pressure sending unit,it's leaking and the light is on.Wondered if there's a low oil pressure cut off built in somehow,haven't found anything on that.Several people have said it's probably the crank position sensor.Did the clutch a few months ago,r&r the crank pos. sensor,I think the problem was before I did the clutch though.Going to double check the harness,original equipment and has 150k+ on it.

2.5 I4, 2wd by the way.

Just used the self diagnostic and got these codes:

1991-95 Models

Code 11-Camshaft signal or Ignition signal-no reference signal detected during engine cranking.

Code 12-Memory to controller has been cleared within 50-l00 engine starts.

Code 55-End of message.

 

[xjrbw]

Dunno about your codes, but I had the same dying / and intermittent re-starting issue a couple months ago. Problem was solved by replacing the CPS.

 

[Matthew Currie]

Code 11 is a crank position sensor code in the 95 FSM. Cam sensor is 54. I'd check the harness carefully, especially if it's intermittent. I don't know how the 2.5 differs from the 4.0, but a Mopar 4.0 of that vintage will stay running with a bad cam sensor if you can trick it into starting.

 

[lawsoncl]

The Code11 means it's seeing the cam sensor, but nothing from the crank sensor. Check that the wiring for the crank sensor isn't melted against the exhaust first.

 

[70 beater]

Thanks for the input guys,it helps a great deal.Harness looks o.k.,going to replace the crank pos. sensor and see what happens.

 

[Blaine B.]

FYI, cam sensor/stator/sync sensor is under the distributor cap. The crank position sensor is on the top driver's side of the transmission bellhousing!

 

[70 beater]

Current status:repaired?

I replaced the Crank position sensor and have taken it for a drive with no problem with the shutting off,so far.I only went about 20 miles or so on the highway and drove around in the neighborhood for half an hour or so,enough to use about a 1/4 tank.I'm not %100 convinced it's repaired yet.
When I removed the original sensor,there was a piece of metal stuck to it,magnetically.Don't know what it was,but I think it was part of the old throw out bearing that came apart.Would that have been enough to cause the problem?
Rechecking the codes,all I get ia 12 and 55 now.BTW,the entire time this has been going on the check engine light never came on to alert of a problem.

I really appreciate the help,thanks guys,
Jon