Champagnecamper

I am having the most infuriating issue with our 96 country. Whether hot or cold the thing will stumble and threaten to stall out after roughly 2 minutes of driving. If i push the (auto) trans into neutral, turn off ignition and restart the engine the problem goes away. It may do this 2 or 3 times in my first few minutes of driving. Once that’s done the thing runs normally for the most part. I’ve replaced the crank sensor and swapped the PCM with no change whatsoever.

Any ideas?

Thanks,
andre

BruceB

I had a similar issue a while back. It ended u being the engine water temp sensor on the thermostat housing. That sensor feeds information to the PCM... I replaced it and had no more problems.

Hope this helps

Champagnecamper

Thanks. I got a new temp sensor and cracked the damn thermo housing putting it in. Better look up the torque spec on that before I put it together with a new housing. I’ll report back once it’s driving again!

Ralph77

I had a buddy who's '96 was running like crap.
Full tune up and fuel filter did not fix the problem.
Turned out it was the temp sensor in the thermostat housing.
That is pipe thread. Tapered so there are probably no torque specs for that.
Just tight enougn.
The Dorman replacement thermostat housing seems just fine cause I used one about 4 years ago and so far so good.
Clean everything up really well including that channel the thermostat goes in.
I recommend using a FelPro gasket here and not the supplied paper one.
With no gunk.
Will be awkward putting it all back together but can be done.
Also guessing teflon tape would be OK but I used this for thread sealant for the temp sensor in the thermostat housing.
https://www.napaonline.com/en/p/PTX7...&gclsrc=aw.ds&
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BruceB

Sorry to hear that, but with these dang Jeeps, one thing always leads to another....they like keeping you on your toes..

Since you are new to the forum here is a link that really dives in to the deep end of Jeep ownership. I know some of it applies to the earlier "renix" Jeeps, but there is a mountain of experience, instruction and advice by the gentleman who wrote.

Have a great day!

Champagnecamper

Thanks Guys, as long as I can get the parts I’ll be tackling this after work today. Bruce I don’t see the link you mentioned!

Ralph77

Just click on the word "link".

Champagnecamper

Oops got it, thanks!

Champagnecamper

Ok I changed the thermo housing just as you specified, fel pro gasket, no rtv put in a new thermostat then new sensor with the thread sealer. First thing i noticed was the engine would turn over but not start. After awhile it did fire up and since then I’ve taken it for a few test drives. It is definitely different. It did fumble requiring a restart once so I don’t think we’ve found the problem but it would have required 5 or 6 restarts before changing the sensor. It seems like acceleration is a little slower than before and idle higher too. On one of the trst drives after the engine had cooled it again didn’t want to fire. I cranked it over over over then turned the key off. Turned it on again and it fired right up.

Any conclusion we can draw from this?

Champagnecamper

I just tried it again. Same odd start thing - no start on first try, key off then starts right up but definitely faltering and stumbling requiring restart.

BruceB

I would try and reinstall the original PCM....

awg

Have you run an OBD2 check/live data scan ?

Champagnecamper

I haven’t. Until your suggestion I assumed it was OBD1 but after a bit of research I suspect it’s OBD2. I have a friend with a scanner so I’ll see what I can learn.

I put the original temp sensor back in this morning and the reluctant start issue went away but still faltering. I’ll switch back the original PCM when I get home tonight.

RocketMouse

Sucks...but at least a new replacement housing isn't going to break the bank. You can probably still source a reasonably priced one even in this age of ridiculous inflation.

BruceB

I would try with the original pcm and the new sensor. You may want to inspect the wire to the sensor....they have been known to get brittle and fray underneath the insulator wrap.. Maybe even check voltage with a multi meter....