Whistling sounds while accelerating N54 '08 535i
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Whistling sounds while accelerating N54 '08 535i
I have an 08 535i n54 stock with 95k miles. Can anyone help with this whistling sound. It only comes on from about 1800rpm to maybe 2700rpm.
I’m hoping it’s something simple and not a major problem. I do feel this all started after a shop changed my valve cover gasket maybe 2 years ago. The car has been using oil since and the whistling sound was mild at first, more so when cold, but recently has gotten much worse.
I’m hoping it’s something simple and not a major problem. I do feel this all started after a shop changed my valve cover gasket maybe 2 years ago. The car has been using oil since and the whistling sound was mild at first, more so when cold, but recently has gotten much worse.
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#5
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Question, will a SMOKE test work with the car idling and get pulled into the Turbo system? The car is cleary making the noise when accelerating and the Turbos are pulling Boost. Wasn't sure exactly what kind of pressure or air flow goes through the turbo system if the car is no accelerating. Wasn't sure if I need a shop that has a Dyno or something to actually test it as the car is "Simulated" driving under load.
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#10
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So, bad news....
No Codes..
Smoke tested, there was a Hose that failed the smoke test, it was kind of under near the air intake on front right of engine bay (While standing facing the engine), I think it's called Turbo Bypass Valve and Hose or something, replaced it, test drove.. same thing. Seems the sound is NOT a whistling, but more of a Whinning. And boost feels very LOW and it ONLY Comes on with Boost. Seems to be 1 or 2 bad turbos or a bearing in the turbo fan or something of that nature.. I think I'm going to move on from this car unless someone has a better idea. I don't know how we inspect the turbos without tearing down a bunch of stuff to get to it and not sure i want to sink more into that.
I'm open to suggestions. I'm guessing retail pricing on turbo install (new turbos + Install is upwards of 8-10k.
No Codes..
Smoke tested, there was a Hose that failed the smoke test, it was kind of under near the air intake on front right of engine bay (While standing facing the engine), I think it's called Turbo Bypass Valve and Hose or something, replaced it, test drove.. same thing. Seems the sound is NOT a whistling, but more of a Whinning. And boost feels very LOW and it ONLY Comes on with Boost. Seems to be 1 or 2 bad turbos or a bearing in the turbo fan or something of that nature.. I think I'm going to move on from this car unless someone has a better idea. I don't know how we inspect the turbos without tearing down a bunch of stuff to get to it and not sure i want to sink more into that.
I'm open to suggestions. I'm guessing retail pricing on turbo install (new turbos + Install is upwards of 8-10k.