So, i'm getting a weird rattling noise that is definitely coming from underneath the car. It never rattles while the car is idle. It starts once i hit about 15-20 mph. Its killing me because I cant figure out what it is! I've put it on a lift and nothing seems to be visually loose. Ive physically checked all the big things that may have been causing it (exhaust, O2 sensor, various piping).

Sorry I dont have an audio file to share. Since it only occurs while the car is moving, the sound gets distorted by wind.

Does anyone have any other ideas as to what this could be?

 

cat shield? any rattle when just reving?

 

couple of things come to mind;
1) aftermarket downpipe banging on the tie bars, especialy if they werent spaced down.
2) there is a small squarish looking plate around the drive shaft, check if its hitting anything.

gl!

 

+1^

That's what mine was

 

+1

 

Mine was the factory downpipe heatsheilds coming loose. I just smacked them off with a hockey stick.

 

No rattling when i rev, only happens once i gain some speed, but Ill take a look at those tomorrow and post results. Thanks for the input so far

 

The downpipe can also be hitting the sway bar above the downpipe

 

I think i might have to add this hockey stick tool to my toolbox.

 

Mine is the heat shield above the drive shaft. It's annoying as heck

 

I'd put it back on a lift and knock on the heat sheilds first.

 

I have 4ich tubing and I know it was touching the heat shield, so I had to remove it. Even at idle it would make noise. As well as ur car's exhaust system slightly moves when the car is in motion. If its stock exhaust could be ur mounts need replacing.How many miles u have on the car? Like one of the members said try removing the heat shield first.

 

78,000 miles on it. Ill check the heat shields on saturday when i can get to a lift. Thanks for the responses so far.

 

I pinpointed the problem.

When i was doing my oil change to day i noticed a piece on the drive shaft that wasnt all the way secure. Not sure what it is but i pushed it all the way back to where it looked like it was supposed to go and voila.

 

Mine has the same problem with the damn downpipe heat shield...
I am way to lazy to get under there after doing the test pipe last month. The problem will get fixed after my BR pipe gets in