Reduced engine power p1516 p2135

[Layton McNally]

I have a 2004 chevy Silverado 2500 with the 6.0 vortec. It throws codes p1516 and p2135 and puts itself in reduced engine power mode. It only seems to happen once the engine is up to operating tempature. I have replaced the throttle body twice. Replaced the throttle pedal position sensor, and searched for broken/ bad wires. I have tried cleaning grounds and other electrical connections and nothing seems to work. Does anyone have any suggestions or experience with this? Any help is much appreciated.

[chem_man]

You might want to read this thread:

 

 

Hope it helps!

 

Good Luck!