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Discussion Starter · #1 · (Edited)
i have been reading and looking everywhere for help.
i picked up this 99 tj 4.0 auto.
it did not have a cat and a second o2 sensor so i replaced those.
then i replaces the tps, cps and the disk in the distributor.
then i replace the plugs and wires.
still have this miss.
if anyone has any ideas i would love to hear them. It
 

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OK I will try to help -

1999 TJ with a 4.0L automatic.
What other codes just the P0320 and P1391?

Could you repost the issue the issue the above post is hard to understand.

PLUGS tell us brand and # - yeah it matters.

A WAG the CMP is out of sync, did you move dist at all when working on replacing cam sensor
 

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Discussion Starter · #4 ·
Thank you for your reply. Auto light was the kind of plugs.
I did not move the distributor.
As far as the codes. Now I just have the p1391.
I do have 5v at the cps. I pulled the plug on thecomputer and checked a4 and a8. No short or anything.
 

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that is vague as the code is for loss of signal CKP on CMP.
I would look at CMP - connector 5v on orandge wire, there is a Brown wire - check to see if there is any voltage on the circuit.
The 3rd wire is signal -gray wire - does it pulse on when checked with DVOM or testlight?

Yu posted "it did not have a can to a second o2 sensor so i replaced those. " WTF could you explain
 

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Is there a CAT on this jeep? I am still confused.

"What is the com" dont understand your question 'com' IDK
 

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the CMP is the cam position sensor - the plate you changed.

TMI
CMP is timed to TDC #1 compression - often it is moved, installed incorrectly and the timing is not synchronized with CPS - term is out of sync, AND a scanner will show deg out of sync.

THe loss of CMP or CKP P1391 - lists a sync issue will set the code, and you menti9ned you replaced CMP SO the question about moving... follow ck of CMP posted in #5 above.
 

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CKP crank position sensor. CMP cam position sensor.

Describe the misfiring you are getting. Slight misfiring at idle? One cylinder dead misfiring? High speed misfire?

The P0320 is no signal from the crank sensor so not surprised that one is gone if it now starts. The P1391 is intermittent signal loss from either the crank or cam sensor. Since you had the P0320 I would guess that the 1391 would be the crank sensor & concentrate on that (P0340 would be no cam sensor signal). Even with that I would not expect a misfire situation, depending on what type of misfire you are getting but normally would expect a P030x when misfiring which would probably tell which cylinder(s) have the misfire unless it is P0300 for general, nonspecific cylinders.
 

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Discussion Starter · #11 ·
CKP crank position sensor. CMP cam position sensor.

Describe the misfiring you are getting. Slight misfiring at idle? One cylinder dead misfiring? High speed misfire?

The P0320 is no signal from the crank sensor so not surprised that one is gone if it now starts. The P1391 is intermittent signal loss from either the crank or cam sensor. Since you had the P0320 I would guess that the 1391 would be the crank sensor & concentrate on that (P0340 would be no cam sensor signal). Even with that I would not expect a misfire situation, depending on what type of misfire you are getting but normally would expect a P030x when misfiring which would probably tell which cylinder(s) have the misfire unless it is P0300 for general, nonspecific cylinders.
Ok. Thanks. On the sensor on the bell housing I do have 5 volts. The middle wire is a ground I think. All I did was check for voltage and continuity. Does not seem like I have a short.
I got rid of the other code. All I have now is the p1391.
I kinda feel like this may be due to buying a cheap crankshaft position sensor

not sure how to tell if I have a miss fire. I have this tool that you unplug the spark plug and connect this wire. It has a light bulb. I tested every plug and it seems to be firing.

the sensor in the distributor. I replaced it with one from my other Jeep what was running find. So I think it is good.
 

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Discussion Starter · #12 ·
Sorry I did not answer your other question.
When I crank the Jeep it runs very rough. Almost stalling at times.
Then I drive it. The rpm’s will randomly spike. As well as run like crap
 
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