Cat Failure?

Dr_Jones · Post by **Dr_Jones** » Mon May 17, 2004 4:36 pm

If anyone that remembers may recall, I have been having some problems with my exhaust. I fitted the UAS pipe and shortly after that I replace the muffler and also two new resonators (nothing to do with UAS pipe by the way) about a week after all this was fitted there was a loud metal rattle noise at idle coming from the Cat or thereabouts. Now the noise has all but gone and the car sound totally different I liken it to someone having there hands over your ears...just sounds really muffled all of a sudden

This change was instant from one trip to the next no gradual change. So could the inside of the cat gone bad and caused the rattle and now be loose and blocking my exhaust. Seems slower too but that could be a placebo coming from the fact that it is so much softer in volume.

Any ideas...will be going to shop with it but just wanted some opinions first.

Cheers
Dan

Post by **smorison** » Mon May 17, 2004 7:48 pm

CAT's are consumable items, i know they aren't commonly thought of as that but they are.

if it was rattling then stopped whatever was loose may have worked its way through your exhaust system and is not stuck in a muffler (not good if this is the case) or passed through like a kidney stone

payaya · Post by **payaya** » Mon May 17, 2004 9:46 pm

give the CAT a tap with a rubber mullet, as lose particles caused by broken off internals stay there.

If you can hear lose particles inside your cat is dead. Cant you take off the FTO cat easily?
might be an option.

Post by **smorison** » Mon May 17, 2004 9:52 pm

payaya wrote: Can you take off the FTO cat easily?might be an option.

sometimes...
depends on the exhaust system they can be welded on or flanged on....

hopefully it will be on by a flange

Dr_Jones · Post by **Dr_Jones** » Thu May 20, 2004 2:16 pm

Well all fixed now...the shop pulled out two potatoe sized pieces of honeycomb from the inside of the pipe....wedged in there real good.

All good now.

payaya · Post by **payaya** » Thu May 20, 2004 3:05 pm

if the cat has melted honeycomb, you might as well get a new cat, as it would be still melted inside.

Dr_Jones · Post by **Dr_Jones** » Thu May 20, 2004 4:14 pm

Sorry should of mentioned now have a new high flow cat installed, doesn't meow though

Also passed the emmisions test with flying colours just to check the other one didn't die for and other reason other than old age.

Also pulled a 101 on the dyno in the process

payaya · Post by **payaya** » Sat May 22, 2004 6:53 pm

Its weird cat failures of real uncommon on FTOs! Its a good thing i guess.

Also its uncommon to see a FTO run lean, they usually run a tad rich.