Robbie Boyd

I started the car up today and I heard a rattling sound which I'm pretty sure is coming from the catalytic converter or something in that area. It sounds like something's broken off or loose inside of it. Looks like its time to get a new y-pipe/headers.

Can anybody give a guy a hand? Could it be something else?

It seems like the car always has something wrong with it, but I guess that's what I get for having a high mileage 'bird.

30AnvZ28

iTrader: (2)

thats what I was saying when my z had 135K miles on her... then i decided to quit dicking with it... and im now building a new motor.

ExtinctBird

iTrader: (1)

There's a heat shield over the cat that is just held onto the body by a few screws. It is possible that it has come loose, causing the rattle.

blind527

iTrader: (8)

Or there is something broken in the cat. Do you feel a decrease in performance?

matrik

iTrader: (5)

I had the same problem a long time ago. Random rattling from the cat area, turned out my cat had gutted itself so i got a high flow one welded in place

blind527

iTrader: (8)

If you had LT's and a cutout you would be in the 12's man

Robbie Boyd

So far it's not a loose heat shield.

Speed Density

iTrader: (38)

my cat smells poopie, when i slam it, i bet your cat has gutted itself. tehehehe

flatlander757

are one of the hangers or flange bolts loose?

Robbie Boyd

nope, not when i took a look under the car.

maedgo

iTrader: (6)

same thing to me, but i bought LT and a y-pipe to solve that problem

Hotwire

iTrader: (1)

GMs and Jeep cats have a bad problem of loosing hold of the ceramic catalyst inside the converter. right now it's probably just lost the fabric pads that hold it in place. pretty soon it'll start rolling around enough to start knocking off chunks of catalyst and either be passed through the muffler or will start clogging your exhaust. Mine got so bad that when I would go around certain corners the catalyst would just about choke off my exhaust, I had to slam on the brakes to knock it loose. This happened every morning for a week until I cut it out and installed a catco high flow converter.

M29_Formula

My cat worked fine up until about a month ago, when at 98,000 miles I un-did my catback and beat the hell out of it with a prybar and a hammer. Wyoming = no emissions.

Robbie Boyd

Is the stock cat just bolted in place?

M29_Formula

Actually, I don't really remember and I'm too lazy to go outside and look underneath my car. I *THINK* on the 93-94 cars it's actually welded into the y-pipe and just has the flange on the rear to bolt to the catback. If you're thinking of getting rid of it, the cheapest solution is obviously just to gut it. I needed a few extra horses to hold me over until I get a nice weekend to do my headers so I put my car on the lift after work one day and gutted my cat. Probably only got me about 10hp, but it's louder now atleast.

blue94

iTrader: (7)

My cat did the same thing. I have a 94 and it started rattling one day. I figured out it was coming from the cat so I just ignored it. it progressively got worse until one day my exhuast actually got much much quieter. I just took it off and gutted it. The catalyst had rattled around so much it had broken into small chunks and was clogging the back of the cat. It is welded in the front and bolted in the back. We just sawzalled it off and pulled out all the chunks and welded it back on. It is much louder now and does not run like crap anymore.

Evaporate

iTrader: (22)

the cat should be welded to the rest of the pipe.

ramairracer

iTrader: (13)

this happened to my cousin last week we got a cutout for it and it didnt sound loud enought and it sounded like it had a rattiling coming out the bottom... it was at night and the car kept over heating and the exhaust manifoklds were even glowing red!! we finally put a new stock style cat and that was the problem now it runs better and the cutout raelly sound good now