Mama_Rizz

Hi, y'all ~ I apologize up front for the long post. What can I say... my baby is a little high maintenance! ;-)
Beginning yesterday, my '97 Cherokee became possessed... sitting at an idle, she started "sputtering". The rpms bounced between 750ish? (The line just above 0) & 1200ish? (The line just above 1). Upon acceleration she bucked and snorted, and the tach bounced up and down, going as low as 0 and as high as 4 grand without the motor actually revving. I felt like I was riding a bucking bronco, and of course, I'm an hour away from home!
I limped her back to where I'm staying; the "check engine" light came on, and she promptly died as I was pulling into the parking spot ... error codes are 12 & 54.
Hubby & I argued over what the 54 was all about... he insisted it that it's a problem with the O2 sensor while everything I've found on here says it's the cam sensor in the distributor.
Long story short(ish), he drove up with my "old" distributor that he had replaced with one from his '93 (don't ask me why). Shocker! The 93 cam sensor does NOT interchange with my '97, so he ended up putting my old distributor back in, thinking it would get me by until I got home. Everything acted normal upon a test drive... until he left and was almost home! She's back to being naughty.
Any help would be appreciated before Hubby comes back in 2 days (the soonest he can be here) so there's not a lot of cussing involved (more than normal, anyway).

Camaroboi13

02 sensor codes do NOT produce driveability issues, I would lean more towards spark and timing, like the cam sensor you're referring to. Even with no 02 sensor hooked up, the car would run rich or lean, but it would not cause the bucking issues you are running into.

lawsoncl

You are correct that code 54 means loss of cam shaft sync signal, but that can be also caused by a failing crankshaft sensor. I also would suspect the the Crankshaft Position Sensor (CPS) because it is a very common failure, and often does not throw any check engine codes.

Mama_Rizz

Update: I decided to take her for another test run and was able to drive about 5 or 6 miles last night after dropping my daughter off at the hospital (grandson born 5 wks before he was done cookin')... Li'l Girl performed just fine.
However, when I got back and parked in the parking garage, I let her idle with the heater on (it's cold here, bro!)... after idling for 10 minutes the tach jumped to 3 and she died. I was there for about an hour before she came back out; Li'l Girl started right up and drove back to the house we're staying at like normal, purring like a happy kitten the whole way.
Could there be a bad connection somewhere? With 3 grandbabies born in December and Christmas, we don't have a ton of $$ to throw at her to figure this out.
Thanks for your help guys ~ You're ah-mazing!

4.3L XJ

Since your tach jumped that high, I think it is your cam shaft position sensor. Your tach runs off impulses from it, so with that jump it is getting too many impulses and in the wrong places

Mama_Rizz

Just a quick note to let y'all know... it was definitely the crank sensor! Li'l Girl has a brand new one and is once again purring.
Thank y'all for all your help! :-D

lawsoncl

Thanks for the feedback. It's always nice to know how thing turned out. I hope you didn't rub it in too much that you were right.