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Discussion Starter #1
First off - I have a CP-E CAI intake so I can pretty much hear the fuel being injected.

Here's the deal:

Part throttle, push the clutch in, a split second later I hear a little "chink" noise. It sounds kind of like if you had two large metal washers and dropped one flat onto the other - CHINK.

It only happens under part-throttle shifts - very low throttle input - just cruising town. It doesn't do it if I'm WOT.

It also doesn't happen in every gear - mostly 1st to 2nd and 2nd to 3rd.

I heard it first with the windows down but now that I know what to listen for I can hear it with the windows up and stereo off.

Anybody experience this? It's definately coming from the engine as it happens 0.5 second (or so) after I shift into the next gear.

Anyhow, it doesn't bother me but I'm just wondering what it is.
 

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pipe hitting the heat shield maybe? the black heat shield that holds the intake in place. you might want to put some buffer there for when your engine rocks.
 

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^^^^^^^ What he said is probably a good guess.... If you are hearing a "metal clank" its unlikely to be anything internal... I can't think of any problems or defects with an engine that could make such a sound... and not have valve springs shooting out the hood =)
 

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First off - I have a CP-E CAI intake so I can pretty much hear the fuel being injected.

Part throttle, push the clutch in, a split second later I hear a little "chink" noise. It sounds kind of like if you had two large metal washers and dropped one flat onto the other - CHINK.

It only happens under part-throttle shifts - very low throttle input - just cruising town. It doesn't do it if I'm WOT.

[/b]
so my first question is if you have a turbo and direct injection, the fuel is only being injected behind a closed valve and IF the sound did make it out into the manifold, the sound waves would have to make it past the spinning turbine... my guess is you are hearing the hiss of the turbo spooling. that being said, are you sure you are hearing metal? perhaps it is a low psi blow off? other than that, I think what was mentioned before is a posibillity. the new intake could be clanking against something...
 

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Discussion Starter #6
Thanks for the replies - this is what I've found:

The CP-E intake is in no way hitting the heat shield - the tube sits perfectly in the middle of the heat shield where it extends into the wheel well.

I grabbed the intake tube and tried to move it around and the only movement allowed is from the rubber bushing.

So I can't imagine this being the source of the noise.

The noise sounds like if you drop a quarter onto another flat.

It happens after letting off part throttle - you can hear the BOV then the noise.

Could this be the BOV - I have a HKS running in recirc.

I never noticed it before, but after listening carefully it's always there on short 1-2 and 2-3 shifts.

Hmm....
 

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Discussion Starter #7
OK - I'm convinced it's the BOV clinking shut - it's gotta be since it happens a split second after you hear it blow off.

I'm suprised nobody else has heard this - you really have to listen close.
 
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