Help won't rev over 4k rpm

[Robert morales]

11 Silverado 2500 6.0 won't rev over 4k rpm in any gear only code is crank shaft relearn which it won't do the relearn because it thinks it's in gear when it's in park  and also  it thinks the brake is being applied when it's depressed it has new  ecm programmed new brake switch new park/ neutral switch   shops around me can't figure it out 

[CamGTP]

Who programmed and installed the new computer?

[Robert morales]

I purchased online and it's programmed to my vin I installed it myself say problem with the old ecm 

[CamGTP]

Ive never seen people have good luck with buying those pre-programmed computers, they always have errors.

 

I go to the dealer or have them go to the dealer so they can program it with the GM tool to the most recent operating system for the PCM and TCM so they are both matching.

[newdude]

17 hours ago, Robert morales said:

I purchased online and it's programmed to my vin I installed it myself say problem with the old ecm 

 

 

If you have the same problem with both ECMs, that leads me to believe the ECM isn't the issue.

 

What codes do you have?  

Edited August 15, 2022 by newdude

[Robert morales]

Yes my thought too how often do the tcm go bad the mechanic thinks tcm might have a short causing it

[davester]

Did the mechanic use a bidirectional diagnostic computer to see what the tcm is doing?  Or just suggesting parts for you to throw at it?

[Robert morales]

Im sure he used a bidirectional scanner he had the truck for a week and I have taken it to other shops and they can't figure it out  I have changed a lot of parts with no difference  I'm sure it's either wiring or electrical  other than that truck runs great  and I can pull my small RV with it out of town