Chevy HHR Network - boost surges

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- - boost surges (https://www.chevyhhr.net/forums/ss-specific-service-issues-repairs-61/boost-surges-59797/)

2009 model - - just turned 70,000 miles today - - - it does have the GM boost upgrade - - - on light accel, the boost will hold steady - 5 -7 psi., if i get on it, about 50 - 70 % throttle, the boost will surge from 5ish to 15 ish - rapidly - - - any idea's why - - i do have the forge aluminum recirc, stock type blow off valve

Do you think that is not expected?

Cracked pipes? Loose clamps?
Clogged air filter?

Did you ever install your new boost control solenoid?

Are you saying itll surge from 5 to 15 and back to 5?

Sounds a lot like the old wiring issue with the turbo upgrade sensor. Have you checked that out?

wiring at the a/c comp is good. has layers of protection. i never did install the solenoid. issue went away at the time. if i accel , it will hold a steady 7 lbs of boost. if i really get on it - it will go from 7 to 15 ish & back to 7, rapidly. i let off , because i don't want to damage anything - - - no check engine light ever comes on

Something is not holding pressure in the system. There is a leak or a bad solenoid/valve. I.E.: something is failing to hold more than 7 psi.

Your problem is to find where the weak point is.

MAF cleaning solved problem

Have a 2010 HHR SS with close to 79,000. Have the Stage 1 upgrade. This car is wild! But starting about a year ago I started getting surging, misfires... P0100 codes (MAF our of range). Turned out the air filter had NEVER been changed... even though the quick change places always said they checked. Changed filters and I was back in business.
Starting a few weeks back the car started slightly surging... turbo gauge bumping around... and generally loss if power (boost). No error codes. In other words, my SS didn’t really feel like an SS. Took it to Chevy with a list of things to check... look for wire chafing, crimp problems, etc ... derived from this website. Chevy, to their credit, said I could be wasting my money because I had no error codes. In particular they thought cleaning the MAF sensor was a needless expense and made sure the service doc said it was at “my request” (no problem... they were just being cautious). At any rate, all looked good to the them. No crimps... all pre-made connectors. MAF readings at idle were “within range” before and after cleaning. BOTTOM LINE: My HHR SS is back. Strong. Quick revving. Steady power to redline. I am guessing that my dirty air cleaner dirtied the MAF. Total cost for checkup and cleaning MAF: $250.00.

well, i finally replaced the boost control solenoid - that is mounted on the turbo - - - car now has 74,000 miles.

what a motherf--- !!! i tried 3 times to get at it at home - -NO WAY! A friend has access to a lift, so, last saturday, we spent 2 hours on it. took 1/2 an hr just to unplug the electrical connector - - it was stuck on there, no matter how much we presses the release wire. have to take off the right front tire to get any access - - sway bar, control arm are both in the way - barely any space to get 1 arm up there & it's a long reach.
anyway - now, on 1/2 to 3/4 throttle - it holds steady at 13 psi & when i give it all from a stop, it peaked at 20 psi - - the old solenoid must have been weak - - defintly fixed the issue !!! :thumb: