Slight hissing sound under WOT...?
Thread Starter
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Joined: Jul 2005
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From: London, UK
No longer stock '06 E55, A3 3.2 Quattro, GLE 400d, R107 280SL, Golf Polo
Slight hissing sound under WOT...?
OK so I got this issue, now I dont know if its something new or mbe had not noticed before. Sounds like a boost leak and I've trippled checked the bolts / gaskets etc.
Seemed to arise when I removed the S/C phenolics... mbe its a misaligned / damaged gasket. I reused the old ones ? Anything else come to mind?
Mbe its just how it sounds now ...
Seemed to arise when I removed the S/C phenolics... mbe its a misaligned / damaged gasket. I reused the old ones ? Anything else come to mind?
Mbe its just how it sounds now ...
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one car at a time
It sounds like a boost leak and since you mentioned changing gaskets - start there....pressurize the system if you want to be 100% sure...
Also, you posted a change in your exhaust (in another thread).....Are you certain you don't have an exhaust leak (pinhole leak from a bad weld) ?
Also, you posted a change in your exhaust (in another thread).....Are you certain you don't have an exhaust leak (pinhole leak from a bad weld) ?
Thread Starter
MBWorld Fanatic!
Joined: Jul 2005
Posts: 3,174
Likes: 19
From: London, UK
No longer stock '06 E55, A3 3.2 Quattro, GLE 400d, R107 280SL, Golf Polo
The exhaust I think is ok as its more a hiss than a tick, and it was there before I did the mid section rework, and still there now.
Might be one of those semi transparent breather tubes that either dislodged or bust
And then it could be the gaskets. They have had a few re-re's in their life.
Might be one of those semi transparent breather tubes that either dislodged or bust
And then it could be the gaskets. They have had a few re-re's in their life.
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2004 E55K AMG Wagon
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MBWorld Fanatic!
Joined: Mar 2011
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From: Orange County, CA.
one car at a time
Not exactly...sometimes the leaks are only seen under boost (vs. vacuum)....Which is why I suggested pressurizing the system....
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From: London, UK
W212 - E63 AMG
I'm willing to put money on it being an exhaust leak. Take it back to that exhaust shop, put it on the ramp, start the engine and feel around the flanges where they worked on/spray liquid. I'll bet that's the problem.
