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Today as I was getting off an on ramp to the highway I tried to accelerate and had no power. Check engine light came on so I pulled over to a safe spot and had onstar run diagnostics. Came back with code P0299. Restarted the car and it seems to accelerate fine if not putting a lot of demand on it, but if I try to get speed quickly I lose power quickly. I googled the code and it seems it’s a underpower boost issue. Anyone know how I can easily check / test what’s going on? Thanks in advance for all the help.
 

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Probably have a leak on the boost side. Start by tightening the clamp on the throttle body.
 
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Today as I was getting off an on ramp to the highway I tried to accelerate and had no power. Check engine light came on so I pulled over to a safe spot and had onstar run diagnostics. Came back with code P0299. Restarted the car and it seems to accelerate fine if not putting a lot of demand on it, but if I try to get speed quickly I lose power quickly. I googled the code and it seems it’s a underpower boost issue. Anyone know how I can easily check / test what’s going on? Thanks in advance for all the help.
Autozone can tell you exactly what it is
 

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What I do when faced with a P0299, is I pressurize the boost side @20PSI and check for leaks. Made myself a little setup to do so.

Around -10PSI at idle so in vacuum actually. Maximum boost I've seen is 13.5PSI uphill in sixth at 110kph. Accelerating onto on ramp to merge is 6 to 7. Taking off from dead stop in the city I'll see 3PSI. You can check for leaks by pressurizing the intake at 20PSI. It should not drop below 15PSI within 0ne minute. If it does you have a leak worth looking at somewhere. When your leak gets bad enough you will get an underboost code ( P0299 ). I made myself this contraption to measure pressure leak in the intake.
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Could be a crack in the intake hose. The Sonic had this as a notorious issue. Even had a service bulletin. Under acceleration, the tube would collapse on itself and restrict airflow

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