V2Rocket

I've been noticing the last week or so a weird annoying rattling noise that sounds like sheetmetal when I accelerate in 1st and 2nd, cant really hear in higher gears because of road noise.

I got under the car and checked all the heatshields and stuff and everything seemed to be tight, not missing any screws. I read around a little bit and the most common places for this kind of rattle are:
1) missing rubber exhaust hanger donuts
2) catalyst falling apart
3) muffler insides coming loose

the exhaust hangs fine so all the donuts should be there, and the catalyst is maybe a year old. Has anyone ever experienced a muffler falling apart on them?

Car is a 1985/1 NA.

krystar

i found a rattle similar. when doing medium to hard acceleration in 1. my issue was the driver side inside rear seat bolt where i had secured my harnesses. the bolt was too long and it was hitting the shift lever somewhere. swapped to a shorter 1" and that fixed it.

thirdgenbird

every once in a while i get a noise like this.

i found it was the pipe hitting the sway bar very lightly.

ilikemy944

Cat gets my vote (mine rattles).

V2Rocket

even though its still pretty new?

DarylJ

.......OK....I'll bite. You've been here long enough to know this: Have you bothered to see if you can reproduce it with various RPMs while sitting still? If so, have you/someone else tried to get closer to the noise while you have been doing so?

ilikemy944

I also have used the bang on the exhaust method to figure out what is rattling.

V2Rocket

sitting still you dont notice it, at least not for the short times ive tried to listen while just parked. ill hold it for longer periods and see if it persists or if its pretty much only when moving

V2Rocket

already passed that test

IGROWL

Did you install the rear tow hooks?

I did and now in 1st gear the muffler just slightly rattles against it for a quick second.

V2Rocket

no, i have an early with no provision for those hooks

kennycoulter

are you sure it isn't a "through" bolt in the exhaust rattling? i forgot to retighten one from the cat pipe to the muffler pipe, and it sounds like a heat shield rattle.
maybe just the compression of the gaskets from manifolds to cat pipe or catpipe to muffler pipe caused a through bolt to be a little looser...

tuanle16

wow. i have the exact same problem. how did you fix it? what was the problem?

tuanle16@juno.com

V2Rocket

it is the biscuits inside my catalyst coming loose

till_that_day

You don't happen to have a Flowmaster do you? In mine, it will rattle around 1300 and 2700RPM. Sounds like a baffle has come loose in the muffler itself.