Q: "Fluttering" noise under heavy throttle/boost

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While driving the car slowly the noise does not occur unless I'm on the highway and in 5th gear under acceleration. But when I step on it, I can hear it right away from 1st gear to 6th as long as my boost is under load, and throttle is pressed down. From my novice UTI schooling, I'm thinking wastegate, D-valve, or something else, I'm not sure honestly. it sounds like a flutter but instead of hearing it after you let go of the throttle you hear it while giving it power and boosting

My car has 8000 miles.
My car has a manual transmission.

Hello, thanks for writing in. If this occurs only under this high load condition then most of the time it is caused by a boost leak. I usually suspect that the intercooler has a crack as that will cause this noise. I also would check the exhaust fittings to the turbo and the intake tubes. If those are fine then it very well could be the wastegate not sealing or an issue within the turbo, but both of those will usually cause a power loss. I recommend having one of our certified automotive technicians from YourMechanic come to your home or office to inspect, diagnose, and repair the issue.

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