zj ? engine codes

[filterbiz]

paging joe peters

the lady was driving down the mountain today and the jeep just shut off. waited like 2-3 minutes and it fired right up. ran fine all the way home and starts right up everytime. i do have stored codes p0320 ignition/distributor engine speed curcuit and
p1391 loss of camshaft crank?

any ideas of what happened and will it happen again! thanks

1997 4.0L 4x4 laredo

 

[Tim_MN]

P0320 (M) No Crank Reference Signal at PCM. No reference signal from crankshaft position sensor (CPS) detected during engine cranking.

P1391 (M) Intermittent Loss of CMP or CKP. Loss of the Cam Position Sensor (CMP) or Crankshaft Position Sensor (CKP/CPS) has occurred.

Test the CPS on the bell housing and inspect the CMP in the distributor. The CPS is probably faulty.

 

[birchlakeXJ]

I agree with Tim that this most likely is a "crankshaft position sensor" problem. VERY common on the Jeep 4.0

Will this happen again? Almost assuredly. Sometimes the crank sensor fails solidly, and other times it becomes intermittent for a period, giving you some time to replace it before it leaves you on the side of the road.

Here is a link to a thread with more info. on this from Tim inside of it.

http://www.naxja.org/forum/showthread.php?t=1044073

 

[joe_peters]

Tim_MN and BirchlakeXJ have you covered on this, sounds like the early stages of a crank sensor failure.

 

[filterbiz]

so i got done golfing today and crank no start. cannot here pump come on and it has 0 pressure at the fuel rail. but still has codes p0320. i no the pump needs to be replaced but what about the 320 code