Overboost and falls off
 

i bought a 2008 HHR SS in November 2018. i was experiencing some issues with the boost. i understand that the stock boost should be under 15 psi. there were times i would see it over this and then i would lose all boost. i decided to to the Turbo MAP sensor upgrade from ZZP with a HP Tuner tune to see if it would solve this issue and it didn't. Now I'm seeing boost over 25 psi with a P0234 code that's over boosting. now from what i read it could be the wastegate or the bypass valve. I'm leaning more to the wastegate. is there a direct replacement? or for those who replaced where did you find it ? i am having no luck in finding a wastegate.

Thanks in advance

Here's how to check your wastegate solenoid :

This is one of the few cases the book blames the sensor for. Do you have the correct sensor for the tune?

https://www.rpm-motorsports.com/stor...-actuator.html
https://www.ebay.com/itm/GM-Boost-Wa...Model%3ACobalt

I thought I had found more.... will keep looking

Thank you. the question is where do i start troubleshooting

Thank you. ill do some reading on this.

i should have the right ones. i got them from ZZP

thats the one thats next to the turbo right ?

Well shoot, the links to full-race for a replacement solenoid are no good, 404. I think they were only $70