I'm getting some kind of high frequency rattle in my stock muffler.
Its almost like a high pitched buzzing. This only started maybe a week or two ago.
It only happens when I step on the gas at low RPMs.
Is this normal? If not what's causing it and how do I fix it?

Your help is greatly appreciated.

 

Sounds like you either have something rubbing agaist your exhaust, a loose heatshield, or a plate has loosen in the Cat or muffler. The only real way to tell is to crawl under and look for rubbing. With the exhaust system cold. Grab a hold of it and try to "shake" the system from various different points. See if you can feel it hit or rub anywhere. If it is not hitting or rubbing, try lightly tapping on the heatshields to see if one is loose. Lastly LIGHTLY tap on the cat and muffler to see if you can tell which one has the vibrating part that is causing you the problem.

 

Thanks I'll check first thing in the morning.

 

Ah, Fixed for the final time! smile.gif

got under the car on Sunday and fiddled with the exhaust, and now I have a rattle free exhaust with a properly centered tip.

Sounds a lot better without that "buzzz-clang" at 2500 rpms.

So no pebble, nothing stuck in the muffler, just my installation stupidity. Well, now I know for the future.

later,
a