Muffler sounds dampened, catalytic converter is rattling....??? - Toyota Nation Forum : Toyota Car and Truck Forums

RichieRichJP · 10-06-2005, 05:13 PM

Recently I've been having some issues with my muffler.
First of all, I've nailed it down to the cat because when I use a stick and put pressure on the upper part, it stops rattling. But it doesn't stop there.
Now when I drive, it sound muffled and so damn quite, I can't hear it over my music at all

As some of y'all know, I have Universal Apex N1 mufflers and those are kinda loud. There is obviously something wrong! My best best is something in the cat is restricting air flow like the shit inside of it somehow broke. I sure as hell don't think something crawled into my pipe haha

fox_prime · 10-06-2005, 09:01 PM

if it sounds like something's rattling inside the cat, chances are that it's bad due to a poor O2 sensor or something. read up on this thread i started a few days ago:

http://www.toyotanation.com/forum/t100012.html

RichieRichJP · 10-06-2005, 09:29 PM

OH I know the o2 sensor is fine, its just the heatshield is loose and its pissing me off! The dampening shouldn't have anything to do with the O2 sensor neither. I'll read on it though

terrastrife · 10-06-2005, 10:45 PM

take cat off and have a look...

ShawnM · 10-07-2005, 06:24 AM

If the exhaust is restricted due to a bad converter, then you should definatly notice it from the preformance loss. Converters can go bad or break apart internally for many reasons. Have you been using cheap gas by any chance?

RichieRichJP · 10-07-2005, 07:51 PM

I use whatever gas there is at the pump. I really do think that the cat is breaking inside, but its weird...When my cat rattles, there is no restriction, but when it doesnt rattle, it sounds really dampened

RichieRichJP · 10-09-2005, 10:55 AM

Well, my car started sputtering today and I looked inside my muffler to find the stuff inside my cat knocking around inside blocking my pipe off. I broke that stuff and it runs slightly better, but now the exhaust smells more gassy and the Check Engine light just came one..FUCK!!!

terrastrife · 10-09-2005, 07:31 PM

hoes doesn an N1 even hold bits of broken cat in it...

RichieRichJP · 10-09-2005, 09:26 PM

Yeah, I ended having to keep revving my and drive it around my neighborhood for about half an hour until it quit chugging. At first it took almost 10 secs to reach 30mph and it kept knocking back and forwards. I even stepped on the gas on time during that and it didn't even push, there was just torque and the RPM's kept going up. Since I probably blew a lotta shit outta my pipe or into my muffler, atleast I can get to work tomorrow

So are magnaflow cats this shitty?
Do you think having a 2.5" cat vs. 2.25" had any factor (which I doubt)?

terrastrife · 10-09-2005, 11:04 PM

a bigger cat will just flow better (remmeber a 3" cat has about the same flow as a 2.25" straight pipe."

cat failures/blockages/wear are usually from bad a/f ratios... too much fuel.

RichieRichJP · 10-10-2005, 07:43 AM

Oh I see...yeah, too much fuel is my problem. Thanks for your help. I'll get on this when I can