Nekroman

Hey dudes so my 2008 Silverado threw this code last night, P0121 TPS throttle position sensor. Anyways, i called a local chevy dealer and i explained to the tech what was happening. I had an idle of 1,500RPM while in park as soon as i shifted into drive or reverse it would be normal. I also asked if i was able to change out the TPS, he said no. He told me that i needed to replace the entire TB assembly. I just want clarification on this issue. Am i going after the right problem or is it something else wrong with the truck? And also, is the tech correct on me having to buy a new TB? thanks guys!

Robert91RS

iTrader: (2)

Tech was telling the truth but you can try cleaning the TB first if you like.

Nekroman

Thanks for replying dude, I actually did clean it out. I didnt use a cleaner but I just wiped it down with a rag. Funny think is after I cleaned it, the RPM's shot up to 1,500 and I couldnt bring her down to a normal idle.

Robert91RS

iTrader: (2)

Try putting a few miles on it and see if the high idle and SEL clear themselves.

Nekroman

Kool thanks Rob, I apprecite the input.

BrutalSierra

iTrader: (1)

yeah unplug your battery your battery for 30mins. Start your truck and push emergency brake all the way down. Put in drive with ac off and let idle for 5 mins. Then do the same with ac on for 5 mins. Then after 200 miles max it should have relearned its settings. If that doesn't solve your problem you can buy a LS7 TB off ebay for 150.

Robert91RS

iTrader: (2)

Nekroman, I forgot to ask you how many miles you have on that rig. The throttle body is covered by the 5yr 100k mile warranty. Im sorry I forgot to tell you that.