Burned out Cat? Blown Header? Gasket? Help
08-13-2009, 05:16 PM
#27
08-13-2009, 05:52 PM
#29
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white and whiter
i have the old evosport equal length header. just the stock cats.
however even when the header was leaking some times ago it didn't make the noise like now after replacing the cam. also when the shop was working on the car they checked the cats as will and all are good. The noise only came after i got the car back btw.
most likely i'll switch to the LET header at the end of this month when my buddy comes back from taiwan.
i'll see if i can record a video when i find my regular digital cam.
however even when the header was leaking some times ago it didn't make the noise like now after replacing the cam. also when the shop was working on the car they checked the cats as will and all are good. The noise only came after i got the car back btw.
most likely i'll switch to the LET header at the end of this month when my buddy comes back from taiwan.
i'll see if i can record a video when i find my regular digital cam.
Last edited by FrankW; 08-13-2009 at 10:22 PM.
08-13-2009, 10:13 PM
#30
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white and whiter
also when I'm going down hill where it usually would pick up speed if i'm in 5th gear. now it doesn't sort of feels like whenever I let off the throttle power is instantly gone and the car slows down. on that long down hill without touching the throttle the car would not pick up speed faster than 45mph where from momentum it would usually gone up to around 60mph by the time the road levels.
and here is a sound recording i just made driving around the block around my house. I've noted where you can hear the whistle noise.
http://www.youtube.com/watch?v=YvqxcK79NUY
and here is a sound recording i just made driving around the block around my house. I've noted where you can hear the whistle noise.
http://www.youtube.com/watch?v=YvqxcK79NUY
08-13-2009, 10:18 PM
#31
weird. that is definitely not the sound i was describing from having a loose intake splitter on there. idk what that is and have never heard it. do you still hear it with the windows up?
08-13-2009, 11:02 PM
#33
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Hard to tell, Frank. Of course, you know I’m about half deaf anyway.
Does it sound like that above 4000 rpm regardless of throttle position – or only when you’re on it? Check your WOT boost to compare with its pre-repair levels. Any other data logging intel to share would be helpful. Seems almost like it’s a (pressurized) intake leak.
Exhaust leaks tend to be farty and are more likely to occur throughout the rev/load range. Just a WAG. :nix:
Does it sound like that above 4000 rpm regardless of throttle position – or only when you’re on it? Check your WOT boost to compare with its pre-repair levels. Any other data logging intel to share would be helpful. Seems almost like it’s a (pressurized) intake leak.
Exhaust leaks tend to be farty and are more likely to occur throughout the rev/load range. Just a WAG. :nix:
08-13-2009, 11:07 PM
#34
Hard to tell, Frank. Of course, you know I’m about half deaf anyway.
Does it sound like that above 4000 rpm regardless of throttle position – or only when you’re on it? Check your WOT boost to compare with its pre-repair levels. Any other data logging intel to share would be helpful. Seems almost like it’s a (pressurized) intake leak.
Exhaust leaks tend to be farty and are more likely to occur throughout the rev/load range. Just a WAG.
Does it sound like that above 4000 rpm regardless of throttle position – or only when you’re on it? Check your WOT boost to compare with its pre-repair levels. Any other data logging intel to share would be helpful. Seems almost like it’s a (pressurized) intake leak.
Exhaust leaks tend to be farty and are more likely to occur throughout the rev/load range. Just a WAG.
Frank, didnt you have work recently done on your car? did it require the removal of the s/c or intake manifolds? maybe new gaskets werent used or the incorrect gaskets?
are you running stock boost?
08-13-2009, 11:37 PM
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Wow, that's interesting sounding. Doesn't sound like SC whine, doesn't sound anything like a header leak or bad exhaust leak. As splinter noted, exhaust/header leaks sound more "farty".haha My header leak sure did.
I still say check your entire intake tract.
I still say check your entire intake tract.
08-14-2009, 06:13 AM
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white and whiter
it whistle only when i'm on the throttle.
i checked the driver side...there's nothing in the airbox clogging...nor anything in the y-splitter.
08-14-2009, 08:08 AM
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And there are no gaps/leaks anywhere along the intake? Something isn't sealed. Since you just had all that work done, will the mechanic that did the work take a look at it for free? Seems only fair if it was fine (in that regard) before taking it in for repairs.
08-14-2009, 02:18 PM
#38
i'd say if you have a gauge, you could monitor your boost and see if you have a boost leak from a bad gasket or something. but i agree with trevor. the mechanic that worked on it should take a look at it for free since he just did all that work and you have another problem
08-14-2009, 03:34 PM
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Sounds like a boost leak my friend. Pop the hood and lean on the plenums and move them around to see if it changes pitch.
08-14-2009, 07:43 PM
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white and whiter
had it checked out again by my shop. no boost leak. header still has the old issue which doesn't cause the sound. YOU GUYS WOULD NOT BELIEVE what is actually causing the sound........
it is my driver side exhaust tips. i'm guessing because of the angle and exhaust velocity it somehow made the driver side tips a giant whistle. now i gotta have that redone.
it is my driver side exhaust tips. i'm guessing because of the angle and exhaust velocity it somehow made the driver side tips a giant whistle. now i gotta have that redone.
Last edited by FrankW; 08-14-2009 at 08:09 PM.
08-14-2009, 11:31 PM
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white and whiter
yea, I chopped off the carlsson tips and custom the titanium tips.
the left side because of the angle or something decided to start to whistle when the exhaust flow reach certain level.
the > kink might be the issue. I'm gonna have it opened up tomorrow.
http://farm3.static.flickr.com/2531/...092e4ef3_b.jpg
the left side because of the angle or something decided to start to whistle when the exhaust flow reach certain level.
the > kink might be the issue. I'm gonna have it opened up tomorrow.
http://farm3.static.flickr.com/2531/...092e4ef3_b.jpg
08-15-2009, 12:07 AM
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The tips look sweet! Amazing the tips were the issue. So much for sticking your head under the hood.lol You couldn't tell it was coming from the back? Glad you got it figured out at least.
08-15-2009, 07:38 AM
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white and whiter
we're only able to tell revving that thing to 4k rpm and hold it there for couple sec and then I was standing behind the car. sound definitely comes from the tips.
08-18-2009, 12:33 AM
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the exhaust tip noise is fixed today.
http://www.youtube.com/watch?v=mMOzv54OisY
