I have a buddy that I'm helping with his 4l80e swapped turbo 5.3 2000 camaro ss. The PCM seems to want to lock the TC almost all the time even though in the tune as far as I can see it should not be until 40 mph in 3rd gear. In the log it shows TCC ?yes? once moving. I made a log and it showed "TCC apply" pretty much as soon as it started moving. I don't know if this is showing ?yes? because it is locked or if its showing yes because its commanding it to be locked.(chicken or the egg what came first?? haha)
It will shift the 1-2 and then lock (feels like a double shift) and same with the 2-3. It appears to unlock during the shifts and relock once in gear creating a double shift feel. It?s not shown in the log above but when I commanded the TCC PWM or TCC solenoid off it didn?t seem to unlock (not sure how that works on a 4l80e tune) I bumped the PCS manually to 20% temporarily and the shifts became very firm (good) and it seemed to stay locked through the shifts now as the double shift feel was gone but the rpm drop was quite a bit due to the TC being locked.
The car is throwing a P0748 but I don't know if that could be from my forcing the PWM to a higher %? Could this code be causing the TCC to apply? It has a pretty loose triple disc circle D that takes 1400-1500 rpms or so before it really starts moving. I don't know if the car may have a bad TCC solenoid or something mechanically wrong. It doesn't apply in first gear since the fluid path isn't open during 1st, which makes me lean toward a electrical issue more than a mechanical. It has a speartech harness and has been segment swapped. It has a startup tune by a very reputable tuner. Thanks!
The log is not a very good one but its attached below.
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