pippo

Hi People,

Well, for about a year I had this annoying rattle under car, and figured it was the cat degrading. At first I tought it was the trans, as I just had it reman'd, but the trans shop said it was fine but suspected the cat.

So, I just drove it and after a year or so, no more rattle. Any oideas as to what could have caused the "no more rattle"?

I have a 2002, EX 2 dr. AT.

Thaks!

pippo

Oh, no noticeable gas mileage problems, no nothing. also, no codes shown on dash.

portaman03

Rusted heat shield.

It Wasn't Me

I was actually about to say that. Mine was rattling like crazy because three of the flanges had rotted. I went ahead and removed it.


However, OP, I think this is the first time someone made a thread to ask why a problem went away rather than what the problem is. Hahaha..

pippo

LOL! Thanks, guys. So, this heat shield that rotted off, what should I expect to see when I get under car? Should heat shield be entirely gone or maybe just some spot weld suspension points broken/rusted off?

Thanks!

It Wasn't Me

Well.. from my personal experience the heat shield was still there, but some of the mounting flanges had rotted, making the whole thing rattle at certain RPMs. The heat shield itself wasn't in bad shape.

There are two halves (top and bottom) with a total of 8 flanges which attach to mounts on the catalytic converter. I just went ahead and cut the heat shield off at the flanges, leaving the mounting tabs/brackets on the catalytic converter in place.

Just give it a jiggle.. you'll know if it's loose or not.

pippo

I get it, IT. I will try that. I guess only thing to be careful about is now you wont have that shield, so dont park on top of a bale of hay, right? (Im assuming it is held together by spot welds)

It Wasn't Me

With or without the heat shield, if your exhaust is hot enough, the hay (or dead grass) will still catch on fire.

It's not held together with spot welds. The two halves (top and bottom) are held to the mounting tabs (brackets) on the catalytic converter with nuts and bolts.

They tend to seize over time and become impossible to separate. After rounding off one nut, I just cut the damn thing off. Hahaha..

pippo

Thanks, Man!

_Phenom_

Glad that mine wasnt the only one rattling

pippo

I dont believe it....rattle came back. Sheesh, so I jacked up the civic, crawled under car, and banged with fist and rubber mallet to see if thatcat's cover was indeed loose like the other members here advised. Man, that plate screwed around the cat is solid! I just cant see how it could be the culprit unless hey, with an engine running, things would shake easier??? (Oh, also, no rust to speak of whichcould degrade that "plate")

Thanks!!

It Wasn't Me

Banging on it might not make it rattle enough. I hit mine once or twice and it didn't really do much. A little squeezing and prying on the cover(s) relieved any doubt that I had, though.

You might also want to check the heat shields that are bolted to the bottom of the car.

It's a bit of a PITA doing it alone, so you might want to have someone lightly step on the gas as you look for the source of the rattle. (if you haven't already done that)

portaman03

x2

Sometimes the exhaust pipe itself vibrates onto the car's heatshields, and causes a buzzing.

pippo

Sory for delay, but thanks, guys. I will try that out.