IN2LXUAL

iTrader: (4)

Hey all, I have a 95 SC300 5 speed with a really annoying rattle under the car. It seems to be between the front and middle of the car. I initially thought it was a heat shield on the exhaust but my mechanic told me that everything was tight.

Then someone told me that it could be the cat, apparently the honeycombs inside can come apart over time. If that is the case, where can I get a replacement?

Has anyone else had this issue?

MrSlopra

iTrader: (1)

Any exhaust shop should be able to replace the cat pretty easily. And yes it very well could be that. Does it kind of sound like something bouncing around in your exhaust? Does the rattle change when you give it gas both at idle and while driving?

IN2LXUAL

iTrader: (4)

Thanks for the response! It's when I'm on the gas that I hear it. You won't hear it at idle

maynanator

iTrader: (1)

did the mechanic check the o2 censors? if they come loose they will rattle like that.

MrSlopra

iTrader: (1)

Mine started out like that. No sound during idle. Eventually it would though. Is it loud enough to be heard/embarrassing while driving through the parking lot? If you can jack the car up and get under it while somebody revs it a little, you can definitely tell where it's coming from. That's how I found out mine was bad.

Candela

iTrader: (1)

I know they sound at the exhaust shop that all the heatshields were tight, but double check on your exhaust, right at the Y where it splits, it has a Y shaped shield with 3 steel clamps, try to wiggle that.

sc400ka

i would check your bearings in the rear dif, and tranny. these can go bad, and a rattle. also this sound will travel up and down the driveshaft as well.

Durrby

iTrader: (3)

That happened to me when I added o2 sensor simulators to fix the CEL for the deleted cats. The passenger one came loose and for the life of me I couldn't figure out what was rattling.

IN2LXUAL

iTrader: (4)

it is loud and you can hear it while im driving down the street, very embarassing!

Ill have the car on the lift tomorrow and hopefully I can find the problem. Im going to try everything that everyone has suggested. Thank you.

Jdm2jzgte

had a simalar experience...replace the resonaters problem solved

biturbo632

Is that a stock exhaust?

A sound like that happened to me when both my engine mount broke.. my downpipe was touching the frame! Nothing was loose! Just no more mounts loll

IN2LXUAL

iTrader: (4)

So it turns out that a bracket on the exhaust was broken and the two pieces of metal were rattling against each other. My mechanic put a couple welds on it and now I have a quiet car again.

thanks for all the suggestions everyone, I hope this thread helps others.