Cat noise ?

toyodaaddict · Mar 20, 2010

has any one ever heard a cat make noise? and no i dont mean meow meow

i got this noise that sounds like the bearings in my transmission have gone to hell and every day this week its got worse and iv gotten more sure it was time for a new trany until today it started doing it at idle and i crawled under the truck and found the sound coming out of the cat. im just blowen away by this, while in the truck it sounds just like transmission bearings.

anyone ever experiance anything like this? (84 toyota)

zukkev · Mar 20, 2010

Yeah, the honeycomb inside has come apart---shut the truck off, and smack it with a mallet; should sound like marbles rattling; time for a new kitty!!! And once that is fixed, make sure it's running properly...a poor running engine can kill a cat in no time...:awesomework:

97f250 · Mar 20, 2010

does it do it more when off the gas and in gear coasting to a stop ..my car does that raddel noise and it is the broken kitten .... i bought a dog and radio volume up and the problem is solved!

toyodaaddict · Mar 20, 2010

97f250 said:
does it do it more when off the gas and in gear coasting to a stop ..my car does that raddel noise and it is the broken kitten .... i bought a dog and radio volume up and the problem is solved!

its at its worsed at 2300RPM any gear.but yeah it does it in gear coasting

toyodaaddict · Mar 20, 2010

so whould you guys recomend buying a new cat or just reaming out the old one?:silly7: (that doesnt sound right at all)

1980cj5 · Mar 20, 2010

Sounds like the muffler bearing is going out to me. :redneck:

JOOP · Mar 20, 2010

Replace the muffler filter and that will clear out the broken pieces.

Replace the cat

toyodaaddict · Mar 20, 2010

1980cj5 said:
Sounds like the muffler bearing is going out to me. :redneck:

thats definitly it!:fawkdancesmiley:

toyodaaddict · Mar 20, 2010

im thinking of hallowing out the inside of the cat and puting it back together but it has an o2 sensor or somthing so im not sure this will work without effecting my engine?

CHOP SHOP · Mar 20, 2010

just holow it out

1980cj5 · Mar 20, 2010

toyodaaddict said:
im thinking of hallowing out the inside of the cat and puting it back together but it has an o2 sensor or somthing so im not sure this will work without effecting my engine?

You can do that or just weld flanges onto a piece of pipe and use that in place of your cat.

KarlVP · Mar 20, 2010

1980cj5 said:
You can do that or just weld flanges onto a piece of pipe and use that in place of your cat.

You could even add an o2 sensor bung to keep the OBD system happy.

ZING!!!!

JOOP · Mar 20, 2010

toyodaaddict said:
im thinking of hallowing out the inside of the cat and puting it back together but it has an o2 sensor or somthing so im not sure this will work without effecting my engine?

your check engine light will come on if its 96 or newer

KarlVP · Mar 20, 2010

JOOP said:
your check engine light will come on if its 96 or newer

I beg to differ.

Ran about 6 years with a hollowed cat and no CEL. :redneck:

toyodaaddict · Mar 20, 2010

JOOP said:
your check engine light will come on if its 96 or newer

the truck is an 84 but my concern is will it effect air/fuel mixture or anything like that? i have an o2 sensor? in my exhaust man and what apears to be anouther one on my cat.cal imissions

traildemon · Mar 20, 2010

as long as you have a muffler to keep some back pressure you will be fine knock that **** out of there. its old enough that its not going to make any difference in the way it runs. it will breath a little better and probably get a few more horsies out of it. :awesomework:

zukkev · Mar 20, 2010

toyodaaddict said:
so whould you guys recomend buying a new cat or just reaming out the old one?:silly7: (that doesnt sound right at all)

Make sure you're area doesn't require emissions testing...

traildemon said:
as long as you have a muffler to keep some back pressure you will be fine knock that **** out of there. its old enough that its not going to make any difference in the way it runs. it will breath a little better and probably get a few more horsies out of it. :awesomework:

Actually with a properly tuned engine, you will notice no difference whether the cat is there or not...If you've ever done a backpressure test---you'll know that the cat provides no restriction, as long as it's not damaged...

traildemon · Mar 21, 2010

zukkev said:
Make sure you're area doesn't require emissions testing...

Actually with a properly tuned engine, you will notice no difference whether the cat is there or not...If you've ever done a backpressure test---you'll know that the cat provides no restriction, as long as it's not damaged...

Its an 84 so it shouldnt need emissions, and its making crazy noises it has to be messed up

toyodaaddict · Mar 21, 2010

thanks for the input guys. i hallowed the cat and every thing seems fine,engine still runs great and no more noises:beer:

1980cj5 · Mar 21, 2010

zukkev said:
Actually with a properly tuned engine, you will notice no difference whether the cat is there or not...If you've ever done a backpressure test---you'll know that the cat provides no restriction, as long as it's not damaged...

How is that possible I know with any cat I have ever seen you can barely if at all see through them, and on a stock toyota with a 3.0 it makes a bigger difference (soundwise atleast) to take the cat out than the muffler.