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Discussion Starter · #1 ·
Trying to figure out a “new” noise that my FoRS has been making. Going to try and give as much backstory to help out, hopefully it’s not too rambly.

Bought a 2017 RS with only 16k on it. It had the Cobb stage 2 kit on it so intercooler, intake, rear engine mount, and a tune. Since I bought it, it always made a high pitched whistle or maybe like someone is blowing over the top of a bottle, just much louder and high pitched type noise. I always assumed it was the intake succing air. This noise really only happened at start-up and low RPM cruising out of my parking spot, around parking lots, down my alleyway etc. I want to say under 2.5-3k rpm.

It started throwing a low boost code, so I brought it to a “performance shop” in the area. It was diagnosed as a boost leak. (Diverter valve rubber diaphragm had a hole in it and my intercooler piping was cracked) We upgraded, if you want to call it that, to a blow-off valve and put Mishimoto intercooler piping on.

After that the guy at the performance shop mentioned the noise that I thought was my intake might be my turbo turbine scraping the turbo housing and that it is concerning to him. He said he’s stopped it from worsening in the past on other cars by putting some type of oil additive in the cars and mentioned that it would take a bit to kick in, if it were to work at all.

I drove it for two days after the fix and at some point got the same low boost code, and with it got an engine air filter restriction code. I parked it soon after because I ended up sick for about four days (in this time the battery died somehow which is why I figure I’ll mention it), and now while driving I notice the noise is significantly louder, happening more while driving at different RPMs (sometimes you hear it, sometimes not), and also making an interesting sputtering noise.

If the code is anything to run by, I imagine I need to clean my intake out. The car is also slightly overdue for an oil change.

Now my question is - What is wrong with my car? And does this sound indicative of a soon to be blown turbo? Or is my intake just dirty and perhaps sucking more air (trying to) because the leak is fixed, making the noise louder.

Codes: P0299(underboost) P1548(engine air filter restriction)
Video of noise as of last night: May 12, 2022

Thank you.
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