Whistling LT1
Whistling LT1 I just got my car back together and there may be a problem. It seems to whistle at idle only.
I swapped in pacesetter long tubes, pacesetter ORY, mangaflow catback, a new opti, plugs,wires, deleted all the emissions stuff, and pulled the intake.
Well the exhaust was the last thing I did so I was able to let it run on open headers. I didn't hear it whistle while on open headers.
After the rest of the exhaust was done. I was able to see/hear it run more. The idle stays steady at 1000 RPMs for about 5 minutes, then drops down to about 700-800 RPMs and stays steady. While it idles it's whistling, but when it's under load it doesn't whistle at all. I retightened my header bolts and it seemed to stop but it came back.
The whistling can be heard inside or outside, hood open or closed.
BTW, I used remflex gaskets so I know it can't be those crappy paper gaskets pacesetter gives you.
Here's the video.
I swapped in pacesetter long tubes, pacesetter ORY, mangaflow catback, a new opti, plugs,wires, deleted all the emissions stuff, and pulled the intake.
Well the exhaust was the last thing I did so I was able to let it run on open headers. I didn't hear it whistle while on open headers.
After the rest of the exhaust was done. I was able to see/hear it run more. The idle stays steady at 1000 RPMs for about 5 minutes, then drops down to about 700-800 RPMs and stays steady. While it idles it's whistling, but when it's under load it doesn't whistle at all. I retightened my header bolts and it seemed to stop but it came back.
The whistling can be heard inside or outside, hood open or closed.
BTW, I used remflex gaskets so I know it can't be those crappy paper gaskets pacesetter gives you.
Here's the video.
Last edited by The Outlaw Kid; May 16, 2014 at 11:36 AM. Reason: Add video
Banned
Joined: Jan 2013
Posts: 588
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From: Las Vegas
I retightened my header bolts and it seemed to stop but it came back.
I would guess a bad header flange surface - not uncommon. U would need to take the header off again and have it resurfaced - or send it back.
Good luck,
cardo
I would guess a bad header flange surface - not uncommon. U would need to take the header off again and have it resurfaced - or send it back.
Good luck,
cardo
Good lord I pray that's not it. But I hadn't thought of that. Is there a way to check it while it's on the car?
TECH Fanatic
Joined: Aug 2008
Posts: 1,740
Likes: 2
From: Nebraska
I just got my car back together and there may be a problem. It seems to whistle at idle only.
I swapped in pacesetter long tubes, pacesetter ORY, mangaflow catback, a new opti, plugs,wires, deleted all the emissions stuff, and pulled the intake.
Well the exhaust was the last thing I did so I was able to let it run on open headers. I didn't hear it whistle while on open headers.
After the rest of the exhaust was done. I was able to see/hear it run more. The idle stays steady at 1000 RPMs for about 5 minutes, then drops down to about 700-800 RPMs and stays steady. While it idles it's whistling, but when it's under load it doesn't whistle at all. I retightened my header bolts and it seemed to stop but it came back.
The whistling can be heard inside or outside, hood open or closed.
BTW, I used remflex gaskets so I know it can't be those crappy paper gaskets pacesetter gives you.
I swapped in pacesetter long tubes, pacesetter ORY, mangaflow catback, a new opti, plugs,wires, deleted all the emissions stuff, and pulled the intake.
Well the exhaust was the last thing I did so I was able to let it run on open headers. I didn't hear it whistle while on open headers.
After the rest of the exhaust was done. I was able to see/hear it run more. The idle stays steady at 1000 RPMs for about 5 minutes, then drops down to about 700-800 RPMs and stays steady. While it idles it's whistling, but when it's under load it doesn't whistle at all. I retightened my header bolts and it seemed to stop but it came back.
The whistling can be heard inside or outside, hood open or closed.
BTW, I used remflex gaskets so I know it can't be those crappy paper gaskets pacesetter gives you.
Just visually nothing appeared worn or loose. I'm gonna hit the parts store when they open for a vacuum gauge.
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If someone can give me a quick run down of how to post a video.
I got a vacuum gauge hooked up. It idles about 19 in Hg. Hold it at 2000 RPM it sits steady at about 22.5 in Hg. Snap the throttle it jumps 25-26 in Hg. Then goes down to the 19 in Hg again. To me this doesn't seem right, after I snap the throttle it should drop right back to 19 in Hg. It doesn't sound like the vacuum leak hissing you would normally hear, like when you pull a line off. It sounds like a dead on whistle.
I got a vacuum gauge hooked up. It idles about 19 in Hg. Hold it at 2000 RPM it sits steady at about 22.5 in Hg. Snap the throttle it jumps 25-26 in Hg. Then goes down to the 19 in Hg again. To me this doesn't seem right, after I snap the throttle it should drop right back to 19 in Hg. It doesn't sound like the vacuum leak hissing you would normally hear, like when you pull a line off. It sounds like a dead on whistle.
Last edited by The Outlaw Kid; May 16, 2014 at 11:08 AM.
I wound up pulling the belt and the noise stopes. I've never heard an accessory or belt make a noise like that. I think it's either the belt it's self or the alternator fan. One of the fan blades has a crack in it that's why I'm leaning towards the fan.
