I am going to try to "write entire" this afternoon to see if its possibly some sort of bug I can Iron out... Otherwise I am at a loss.

 

Ive noticed a lot of "weird" things lately with hptuners and tunes having odd symptoms or problems, not just you. I know on a truck I am working on that is the case as well as Jake frying his as you know. Just seems to be on the uptick lately.

 

I hate HPT 3.0. If this is a bug I would not be surprised in the least.

 

You know HPT is on version 3.2 now... and Jake was running an old version of software 2.24. I believe his issue is the hardware itself as he described it. Apparently he tried swapping out the cables with no luck either.

I have never had any of these issues with the Gen 3 PCM.

The E38 is a different story... I bricked 2 of those last year with HPT in version 2.24

 

Just to ***** up Rob's thread, my issue on a gen3 pcm is torque management is wanting to pull out tons of timing at a stop in gear at an idle but only when I have my foot on the brake. No clue on that one.

 

Send me a log of this if you have one. Curious.

 

Man WTF!!! This god damn issue just won't quit. I don't get it for the life of me.

Happens absolutely regardless of gear or load at exactly 1400 rpm. That means any forward gear. In drive while brake standing, in neutral while not moving, on decel... You ******* name it. Is it an injector misfire? Is that possible?? I just can't see that being the case since it happens on decel too

 

I don't have any experience with tuning so take this as you wish, I do have a ton of experience diagnosing GM vehicles and it sounds more like a crank or cam sensor issue... Both injectors and ign coils are very load sensitive. Cam and crank sensors are more rpm sensitive.... can you graph your crank and cam sensor? Have you tried another ECM??? Like I said, just a suggestion....

 

Frankly I don't know how to log that stuff. I would think I would have some sort of engine code if one of those sensors was off, wouldn't I?


I don't know. I like where your head is though. This is so dead nuts consistent at 1400 that I need to start thinking along those lines. I have to agree injectors seem to me like engine load would have a massive effect on how noticeable the problem is.


I have not tried a new ECM but I am starting to think I may need to. I just don't understand it.

I'll poke around HPT to see if I can log those parameters for the hell of it.

 

So you have swapped back to the GM TB, you've done a write entire. Have you checked all your grounds? Grounds do weird ****. My next step would be definitely to write a fresh PCM. Also, I've seen a noisy crank signal do some weird ****. Make sure your alternator wiring is isolated and not laying across a ground or something. RF noise is a bitch to deal with. You can check for it easily with a meter. Set it to read Mv, check for voltage on a ground circuit. If it reads anything more than .002/.003, it may be excessive. I'm not sure what the GM tolerance is anymore, but that's sorta my rule of thumb.