Reduced engine power only after startup

[speedmachine]

Hey guys, my Tahoe's been throwing error codes (P0220, P2135, P0120) and going into limp mode but only immediately after starting, not while driving. I already replaced the TPS and pigtail about 6 months ago and had no issues until the other day. Had the same codes and problem then except the truck would go into limp mode while driving. Could the whole throttle body need to be replaced now? Or maybe one of the wires I spliced came loose? TB is clean and the truck runs great otherwise. Thanks in advance

 

[speedmachine]

Bump! The problem went away for a while but has returned..

 

[4WDTRK]

Any chance your foot is bumping the pedal in the opposite direction or a floor mat is causing issues? Only time I've had it happen is when I've accidently got something under the pedal and pushed it the wrong way.

 

[speedmachine]

If anyone's interested this has been resolved after a $350 trip to the dealer. Turned out to be the wiring BEHIND where I spliced the pigtail to the TPS in. Five faulty wires, I just had them replace all eight. If anyone's getting intermittent P0220, P0120, P1516, P2135 I suggest checking these before replacing expensive parts like throttle body, TAC module etc.