P0121 DTC on a 2004 RC / HELP!

[kray]

Has anyone else run into this problem? Installed a sbtb a few months ago and have a Tori tune but other than that nothing else has been done to the truck. Any ideas as to what the most common cause could be? I'm assuming someone has had to deal with this issue in the past.

Any advice would be greatly appreciated.

 

[SRT2SLOW]

Put stock tune back first to see if it goes away.

 

[VENOMOUS1 RACING]

I'd say you likely didn't clock TPS correctly or it's unplugged? Reset codes with SCT and see what happens.