TPS and low boost codes??

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Pujols5

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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!

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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

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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!
 

Hey Vern!

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PoManNox

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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!
Awesome! Glad you got it sorted and followed up for us!

I've seen 2-3 reports of the P0299 code reported in the past few weeks on 2018+ 1.5Ts.

What happened to the OEM charge air cooler if you don't mind me asking?
 

Michaelbeaus

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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!
I think I might be in the same boat. I replaced both hoses, and cooler, even went to larger o-rings, as it still showing the code for me, and I bought my charged air cooler off eBay. Is this the plug-in on the right side as you look at the front of the car?
 

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