RPM Drop and stalling at operating temps

mcarpani

New member
Looking for any technical help possible. 1997 Wrangler 4.0l Automatic, runs fine until it gets to operating temp then rpm drops and it stalls out but corrects itself for a second, stalls out again and corrects itself. I have done a ton of research online and changed the Crank Position Sensor, changed the Distributor with the Cam Position Sensor, cleaned up terminals, checked fuel pressure. Now I am at a loss, anyone has any issues like this? It idles fine, runs fine cold but once it hits running temps it starts stalling out. I have a code reader and I get P1391 and P0320 every time. Again any suggestions would be helpful. Thanks in advance!
 

There are no other codes?
Looks like an intermittent loss of signal.
You used a scanner? - key on off will not show all codes.
But with those 2 codes you want to check CKP - the connector and wiring, shake tug harness when testing ....
Do you need a wiring diagram?

FYI If you replace CKP get part from jeep.
 

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Check crank position sensor??

Sent from my XT1609 using Jeepz.com mobile app

Current condition, starts up and idles normally, it will even drive normally until engine reaches 190 degrees (normal operating temps) then stalls, drops rpm, sputters out and eventually dies. It will easily restart after it dies but immediately starts dropping rpm’s and sputtering out until it dies.
Symptoms occur after the jeep warms up to normal operating temps of 190 degrees.
Changed the Throttle Position Sensor, Crankshaft Position Sensor a second time, checked fuel pressure to rule out fuel pump or filter and all normal at 49 psi at all times, even while jeep was hesitating, sputtering and surging, the gauge remained at the normal 49 psi.
Swapped the ignition coil and the jeep idled normally and thought the issue was resolved however after some time the issue cropped back up, but the new coil definitely seemed to help the issue, the sputtering out and stalling was not bear as bad.
 
Current condition, starts up and idles normally, it will even drive normally until engine reaches 190 degrees (normal operating temps) then stalls, drops rpm, sputters out and eventually dies. It will easily restart after it dies but immediately starts dropping rpm’s and sputtering out until it dies.
Symptoms only occur after the jeep warms up to normal operating temps of 190 degrees.
Changed the Throttle Position Sensor, Crankshaft Position Sensor a second time, checked fuel pressure to rule out fuel pump or filter and all normal at 49 psi at all times, even while jeep was hesitating, sputtering and surging, the gauge remained at the normal 49 psi.
Swapped the ignition coil and the jeep idled normally and thought the issue was resolved however after some time the issue cropped back up, but the new coil definitely seemed to help the issue, the sputtering out and stalling was not bear as bad.
 
check for wire chaffing at the indicated area -
wil follow up thursday
 

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Only use OEM parts. CKP should have had a paper gasket on The tip. Without it you will insert it too far and on first start damage the part.


Check that your distributor is not loose. Take the cap off and verify the shaft the rotor sits on does not wiggle. If it does you need s new distributor.

The TCM connections could be corroded. Any corroded connections will lead to issues.

If they do not work:

Check your 02 sensors. They are not fully used until above 160 deg.

Also check your temp sensor. It sounds like it is going into limp mode sporadically. If the PCM thinks it is overheating it will shut the engine down. Does it start immediately after stalling?


Regards,
JPNinPA

Sent using TapTalk
 
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