CASE (re)Learn won't comnplete...

[NTrails]

I've gotta '99 GTP... basically stocker... It's been throwing a Random Mis-Fire code {P0300) for quite awhile now, even tho' it's not really mis-firing. The PO told me when I bought it that he had replaced the harmonic balancer... when asked why, he said "'Cuz it was broke..." I thought that sounded strange but bought the car anyhow. As it turns out, he never did a case learn after replacing that part... it's required as each balancer is slightly different and placement in relation to the CKP sensor isn't exact. So I borrowed a friend's Snap-On scan tool and was able to get to the re-learn procedure. I followed all the on screen instructions, revved up the motor, and all it says is "Waiting for Full Throttle" and it won't ever complete. It'll rev right past redline if I allowed it to!! So I took it to the stealer as all I wanna do is get the car to pass SMOG and sell it, and I figured the stealer could bang it out in no time. Well they can't... they've had the car for over 6 weeks now... called GM Tech Line... had a GM engineer in the shop and consulted him onnitt as well. I was also throwing a "Desired Torque Request Circuit Level Out-Of Range" code (P1371??) so they wanted to replace my EBTC module at $379.00... I told em I'd source the part and bring it to them ($119.00 offa the .net). That code is gone. But still no case learn. They said it must be the balancer itself or the ECM... I thought theres little to go wrong w./the balancer, so they said a new PCM is $450... again, I sourced and supplied them a good, re-flashed one for $100. Still won't go... So he said he wanted to try a Genuine GM balancer for $327... I got him one offa the .net for $115. Upon removing the existing one, they noticed slight differences in the two, so he ordered one direct from GM (on his dime) to compare to my new one. They looked the same, so they installed it. STILL NO CASE LEARN COMPLETE!!! Now he says he doesn't know what it could be. The "engineer" said its either an internal skip... like it jumped timing or something... I reminded him THAT IT'S not actually mis-firing!! It starts right up, runs strong, gets descent mileage, etc., so that scenario makes little sense at all. The "engineer" said it only could otherwise be the CKP sensor itself is bad. I asked him "Aren't there like 5 or 6 codes specifically for the functionality of that sensor?". The service manager says,"Well HE'S the engineer!!" He stated further that they were gonna continue doing diagnosis-type stuff onnit, and he'll let me know how its going.

I know it's gotta be some dumb little sensor thats requisite for the re-learn to complete thats not listed in the service manuals. I don't wanna keep guessing which part it might be at over $100 each!! But thats all I can do!! I'm gonna gett him a CKP sensor first... then mebbe a TPS sensor. I've already done the MAP sensor, IAT sensor... That's all I can think it could be.

 

PLEASE.... Has ANYONE in here heard or had anything like this occurring before?? I'm certain that my car isn't "unique" in the world... This HAS TO have happened before to SOMEONE!! I just gotta FIND THEM and what they did to resolve it!! I've scoured all the boards and posted on several as well.

 

Please reply with anything that might help with this issue. It'sa good car... in good shape... but I gotta new G8 GT and the GTP has gotta go!!

 

Thank you in advance,

 

NTrails

[AL]

Thats a very strange problem... I wonder if the tech tool itself isnt reading something it should be reading

[mfewtrail]

I'm surprised the "engineer" can't nail this down to a specific issue for you. Are any codes present when they're attempting to do the relearn? Any powertrain code besides P1336 is going to not allow the CKP relearn process to complete. The coolant temperature needs to be above 158*F(70*C) as well. Any technician or that engineer should know this already though as they can read that information in about 30 seconds if they just look at their repair software.

[NTrails]

Yaa... we've got all codes gone off of the PCM.... but it'sa "Catch-22" situation. Because the re-learn procedure won't complete, the PCM is using the 36 pulse baseline off the ORIGINAL balancer, therefore it thinks its mis-firing... so a "Pending" P0300 is set. It doesn't post the code to memory as it'sa pending code, but that's what's prolly causing the re-learn procedure to not complete. It's strange, tho', as it doesn't "Fail" thtry!!e process... it just never completes!! I wish it would throw a P1336... mebbe then it would complete! How can I "Erase" the stored baseline 36 pulse value table from the PCM?? Might that not cause it to complete??

 

Yeahh!!! This might be the ticket to getting it done!! ANYONE!!!! How can I erase the CKP comparitive table from my PCM memory?? Why hasn't the stealer thought of this approach?? DAMMNN!!!

 

I'm headin' over there now to bend that mo-fo's ear a bit... Thanks guys.. and post any other thoughts/ideas I might try...

[NTrails]

The dealer has tried several different Tech II scanners, and I originally tried a Snap-On scan tool (don't remember which model it was...) and they all get the exact same results. Now we've even changed out the PCM itself... giving it a fresh re-flash (twice, actually). I know it's something stupid... we just gotta stumble upon what it is!!! Thanks for your input tho'....

[BXX]

Check the entire wiring harness for the CKP, they are known to rub and short out or get breaks in the wires.

[NTrails]

Check the entire wiring harness for the CKP, they are known to rub and short out or get breaks in the wires.

 

 

If that was happening, I gotta feeling it'd be throwing a code for that sensor being either shorted to ground, or hi/lo voltage, signal out of range.... nthere's like 6 or 7 for it. Also, wouldn't it be running like crap if this were happening? Or at least be running in an open loop condition??