Blow Off Sounds
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Blow Off Sounds
I own a 2000 Z28 and it seems to me that every time the car shifts a "blow off valve" type sound is coming from under the hood....it is easliy heard from the inside of the car....anyone know what this is?
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Hey Spy. Well I looked into that and found no leaks or backpressure problems...It only happens when the car shifts gears and it is loud...people who hear this when I pull up think I'm tubo'd when I'm stock....I just hope it's not doing anything harmful to my engine
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I have developed the same noise.When I let off after a WOT blast it does it.I don't know where it's coming from either. At first I thought it was a belt or something but that doesn't make sence.My QTP cutout whistles a little under wot, mabe it does the blow off sound too.
Keep us posted.
Jay
Keep us posted.
Jay
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Originally Posted by shawnmce2
I own a 2000 Z28 and it seems to me that every time the car shifts a "blow off valve" type sound is coming from under the hood....it is easliy heard from the inside of the car....anyone know what this is?
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yeah it most likely is intake noise but the thing that sucks is it only does it under load so I can't just park it and let the engine run to allow it to happen, so we'll probably never really know what that sound is...as long as it isn't cauing any harm to my engine or it's performance I can live with it...but if there are any people out there that may know please feel free to input...it's goood to get the ideas flowing
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If you hear it at WOT it could be valve flutter. I know every once and a while at WOT when I get it up to 6k my valves float and it's very audiable. It, to the right ears, could sound like a BOV.
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well it happens when I am driving normal and don't have to have my foot on the gas...it happens just as the car is shifting gears ( I have A4) It's louder when the engine is hot than when it is cold
#15
do u have any sort of tranny mods? a few cavalier guys who were running high tranny line pressure would get the same noise when there car would shift. sounded like a bov when the car was under load, and the tranny shifted.
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There are no mods done to the tranny or car what so ever...The car is completely bome stock. I've had the car checked out by mechanics as well and they can't seem to find a problem...they say the car is mechanically sound....
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Yeah, I went on another drive in it today and started looking at other parts of the car and noticed that when it did "blow off" my lights would also flicker at the same time
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Same thing here as well. Only hear it though right after lifting from WOT. But not all the time, only occasionaly. Even at speed it is loud enough to here over road and engine noise. Sounds like a burst of air pressure releasing suddenly from somewhere under the hood. Have had the car for 8 months or so. First noticed it a few months after I purchased the car. Cannot remember for sure if I noticed it before the lid was installed.