4L80E & TH400 Tech.

[aggie91]

Chris

I have more of a programming question than a mechanical rebuild question for the 4l80e.

The set up is a 5.3 running off a 2000 Silverado PCM. We did a segment swap to change from a 4l60e to the 4l80e. Followed the wiring changes needed as found on LT1Swap.com.

The truck idles fine in park or neutral, but stumbles and dies when you put it in gear. From past experience with a TH350 doing this, it would lead me to believe the convertor is to tight and loading up the engine. Before going to that point and swapping convertors, we have some other thoughts/questions.

When we shift the trans to drive or reverse, the notice the O2 sensors nearly stop working and then it dies. If we add 1-2% throttle, we can keep it running.

How does the electronics of the trans interface with the PCM? Does shifting it to drive electronically effect some part of the tune for the engine? If so, what parts should I look at?


Thanks!