cats cool at different rates?

[WradDad]

All,

I was under the car this weekend, and noticed that the cats cooled at drastically different rates.

I had just come back from a drive, and both cats were too hot to touch when I first put the car up on stands. About two hours later though, the passenger side cat was still warm, but the drivers side cat was stone cold! Ambient air temp was about 65 degrees inside the garage.

The car seems to have plenty of power, and I haven't noticed any other indications that there's a problem. I have noticed that above 5000 RPM, I can hear a kind of a roar (as opposed to growl ;-) ), as though the engine isn't breathing as well as it should.

Could the cold cat be blown out, or the warm cat be clogged (or both!)

Thanks in advance for your help.

Barry

 

[WradDad]

Update...

I believe that the driver's side cat has blown out. I remember hearing a fairly loud rattling sound coming from either under the hood, or under the car, while I was out driving. By the time I could find a place to park and raise the hood, it was no longer rattling, and I never heard it again.

I stood behind the car tonight, while my son revved the engine, and I can definately tell a difference in the sound coming from the driver's side. It sounds more muted than the other side. There's also less air coming out of the driver's side pipe.

So, I guess I need to know what's the best way to get all that junk out of my exhaust pipes? Any suggestions as to the best place to get a couple new cats (might as well replace them both)?

Since this car is my daily driver, am I risking damage to the engine by driving it with a semi-clogged exhaust system?

Sorry for the long post and all the questions, but I'M PANICKING!!

 

[Ken]

Re: Update...

I'M PANICKING!!

:L Don't panic.

"There you go man.
Keep as cool as you can.
Face piles of trials with smiles."

Seriously, unless you have modified the system, standing behind the car to tell if there is a difference between right and left side exhaust will do you no good; the two pipes from the exhaust manifolds merge into one in the transmission tunnel, then split again into two separate pipes after they leave the tunnel. I guess I should say that they merge into one cross-flow resonator, then back into two pipes. There is no way to differentiate between right and left banks.

You won't necessarily damage the engine by running with one cat plugged or plugging, but your performance will definitely suffer. If they both plug off you will lose all power and the car won't get out of its own way; it's like the old trick of stuffing a potato in the tailpipe of an unsuspecting rival. :L

Take a look into Random Technology or one of the other aftermarket suppliers.

 

[WradDad]

OK, deep cleansing breath....

Whew!

Thanks Ken, I feel better about the situation now. I had planned to drop the exhaust system anyway in a couple of weeks, to install a Hurst short-shift kit. I guess I’ll just tip the pipes upside down and see how much junk falls out!

I was reading a couple of old posts last night, and someone mentioned that a blown-out cat on my ’96 would throw a code. That hasn’t happened here, so now I’m scratchin’ my head over this! :confused

Thanks again!

Barry

 

[tazdevl35]

No junk will come out of a cat if its clogged only if its broken up. However you can do damage having a clogged cat due to increased cylinder temperature(the car will ping as well) not to mention it can be a fire hazzard. IMHO if it was me I would be getting a new HI FLOW cat setup for your car and replace all the cats. I have seen this before..Corvettes seem to do this from time to time especially the ones with pre and post cats.


Just my .02 fwiw..

Taz