TPS and low boost codes??

[Pujols5]

Has anyone had any issues with getting a P0121 for the throttle position sensor and immediately following that code a p0299 for turbo underboost condition? I can clear the codes and drive about a mile and the check engine lights comes right back on and the Equinox goes into reduced power mode. The codes seem to come on together but I haven’t read anywhere where they are related.. I’ve throughly checked the intercooler and all hoses and pipes for vacuum leaks and everything looks good.

 

[Hey Vern!]

I would start with the TPS. You should be able to check resistance with a multi-meter as you move the throttle plate. If it jumps around TPS is bad.

 

[Pujols5]

Hi. It was the new intercooler. I purchased a cheap eBay intercooler and finally found where they hadn’t drilled the hole out inside the port for the boost sensor. I was mad and glad at the same time Thanks for your response!