4l80e stuck in limp mode?

[arbboyd]

Yes, the check engine light comes on as soon as you turn the ignition on and remains on. Disconnecting power dose not reset it either. Will come right back.

 

[arbboyd]

Have a new ecm on the way this afternoon. Going to drop the pan and check the internal harness and ohm out the solenoids too. I'll update shortly after. Thanks for the advice everyone.

 

[arbboyd]

Just a heads up. Replaced the ecm with one from O'rieilly's and it fixed my shifting issues. Have all gears now. Thanks to all. Also my check engine light is gone for now. Going to do some data logging and see what's going on.

 

[arbboyd]

Wanted to update one more time. In addition to the ecm being bad it was also out of time. Was advanced to around 16 degrees. Bought a timing light, set it at 4 degrees and it runs like new.

 

[Supercharged111]

Did you unplug the wire to set timing? With everything plugged in 16 sounds right.

 

[arbboyd]

Yes, unplugged the wire. Ran like crap at 16. 4 degrees, per the manual, smoothed it right out.

 

[Supercharged111]

Good deal.