[2fast4u]

My car has 2000 miles currently, heard noise around 1000 mile mark. The noise is a rattling sound that comes during deceleration. Clutch can be pushed quarter, half, full, or not at all and same sound. I can start car in morning after around 12 hours since last ride and it won't make the noise. Drive about 2 minutes and noise appears which makes me think it's heat related. I can be sitting still in car in neutral, rev to about 3000 rpm and no noise. After I get completely off the throttle and once the exhaust quites I can hear this rattling noise. It stops when rpms go back to idle. Same situation when I'm driving at low speeds and rpms. When I let the engine slow me down the noise is apparent. Have any of you experienced this? Someone on corvette forum has similar thread, sounds like same problem. His dealer put complete new exhaust on and noise was still there. It makes me think something is loose in transmission, it sounds like it is coming from rear of car but not positive. Any advice would be appreciated.

Thank you,
Todd

 

[ZeeOhSix]

I can be sitting still in car in neutral, rev to about 3000 rpm and no noise. After I get completely off the throttle and once the exhaust quites I can hear this rattling noise. It stops when rpms go back to idle.
Thank you,
Todd

Sounds like something associated with the exhaust system to me. If you can hear it while doing the test sitting still like you describe above, then it can't be associated with the tranny, unless it's something the tranny would do in neutral too.

My suggestion is to have someone put on some heavy leather gloves (to prevent burns) and have them grab and hold the exhaust system in different locations (mufflers, tailpipes, etc) while you do the sitting still rev test and see if that makes the noise go away or change in anyway.

 

[fcalmes]

Tranny noise is common. Sounds like BBs in a boxcar.

Not sure this is the problem, but tranny rattling is common nature of the beast.

 

[ZeeOhSix]

If its the tranny rattling, then it should be noticably different in neutral with the clutch depressed, then not depressed. If the rattle is the same with or without the clutch depressed in neutral, then I'd say its the exhaust system.

 

[2fast4u]

Thanks for the help guys. I will try the leather glove trick tonight!! I really don't think it is the BB noise because I do hear the BB noise while pulling out in first but who knows. This is my first corvette so I'm not used to the normal noises!! Thanks again.

Todd

 

[racingfast]

another sound

I have a different sound.....:-? I would call this like smacking a 55 gal drum with a pipe; its a hollow sound, kinda like a gurgle too.. now stop laughing, I am serious...it does it at idle or moving along at 30-45mph at a low rpm. And not consistant either. No performance decrease was noticed. AM not too concerned, ...... or should I be? :roll:

 

[pmontelo]

Re: another sound

I have a different sound.....:-? I would call this like smacking a 55 gal drum with a pipe; its a hollow sound, kinda like a gurgle too.. now stop laughing, I am serious...it does it at idle or moving along at 30-45mph at a low rpm. And not consistant either. No performance decrease was noticed. AM not too concerned, ...... or should I be? :roll:

Maybe your gas tank is expanding or contracting as the car warms or cools? I haven't noticed this noise on mine, yet.

 

[racingfast]

gas tank burp

pmontelo... I thought of that... some kinda vapor lock sound.. until it leaves me sit, I guess it will be ok. Thanks!