ive been having issues with my exhaust lately.. after a really short drive it gets REALLY hot, and makes heaps of pinging noises when you turn the engine off.
while driving, if you get about 3000rpm it starts to rattle/resonate, and if you floor it, it really badly rattles/sounds tinny.
i have had a noticable performance drop as of late too.

my suspicions are that my cat has collapsed and is blocking a lot of flow, but this is only a semi-educated guess. if someone could suggest likely/known causes, and ways to diagnose them that would be great.. fail getting an answer, ill be pulling my cat off at some point this week and bashing the crap out of it to see if that helps.

ta,
Damon

If it was the cat, you'd be able to smell it! Smells like rotten egg gas.
If it rattles, could mean any part of the exhaust is loose. On my TR i had something similar if not the same to what you're describing and it turned out to be the exhaust manifold.

I had a a completely buggered cat it got hit buy something and put a huge dent in it, it was being replaced with a hi-flow cat at the time, anyway the muffler guy said the inside had completley collapsed, but I wasn't getting any of the symptoms you are. I think M4DDOG may be onto something.

i think may be one or more part of ur exhaust has burnt out. have it checked at a exhaust shop

If it was the cat, you'd be able to smell it! Smells like rotten egg gas.

They only smell like that when they are new.

does it sound like a tractor? if so then its your exhaust manifold. if the insides of your cat collapse, then you will have better flow so there wont be a lack of power. maybe a hole in the muffler???

give your muffler a tap with a screwdriver handle and see if it makes a rattle like it has loose metal inside. if so, you need a new one.

They only smell like that when they are new.
Sorry but mine is 60k kms old and has only just started smelling like it, my cat is stuffed I know. Hasn't effected exhaust flow all that much i don't think, but you can definitely smell it! Especially on WOT.

Sorry but mine is 60k kms old and has only just started smelling like it, my cat is stuffed I know.


my cat was 14 years wen we had him stuffed, smells pretty bad now too!...poor mr whiskers, died of old age :cry:







:bowrofl: sorry guys

Sorry but mine is 60k kms old and has only just started smelling like it, my cat is stuffed I know.

How do you know?

dude get yourself a stainless steel cat converter, high flow preferably, trust me you will never look back and will most likely last you a lifetime!! i had mine installed a while ago as my factory cat was having a few issues, i was going to replace mine with another factory one, but the high flow was pretty much the same price as the factory cat and it went well with my redback system, nice sound and picked up in performance aswell!!

good luck!

How do you know?
Multiple times complaining of the smell and multiple people telling me it sounds like the cat converter, going to an exhaust place and them checking that the cat was indeed stuffed confirmed my suspicions. It just means the cat is not doing its job in getting rid of the nasties and thats what stinks.

ive been having issues with my exhaust lately.. after a really short drive it gets REALLY hot, and makes heaps of pinging noises when you turn the engine off.
while driving, if you get about 3000rpm it starts to rattle/resonate, and if you floor it, it really badly rattles/sounds tinny.
i have had a noticable performance drop as of late too.

my suspicions are that my cat has collapsed and is blocking a lot of flow, but this is only a semi-educated guess. if someone could suggest likely/known causes, and ways to diagnose them that would be great.. fail getting an answer, ill be pulling my cat off at some point this week and bashing the crap out of it to see if that helps.

ta,
Damon

When my cat collapsed a few months back, big chunks of honeycomb came away from the wall and were rattling around inside the body making a hell of a noise. The sound you're describing sounds more like the engine is pinging badly, which combined with the heat issue could be a result of it running very lean.

I'd get it looked at before you do some damage to the block or pistons.

...actually which part of the exhaust is the cat?

...actually which part of the exhaust is the cat?

The furry bit with the tail...

:bowrofl:

nah, it's the boxy thing immediately behind the headers.. forward of the front seats

ive been having issues with my exhaust lately.. after a really short drive it gets REALLY hot, and makes heaps of pinging noises when you turn the engine off.
while driving, if you get about 3000rpm it starts to rattle/resonate, and if you floor it, it really badly rattles/sounds tinny.
i have had a noticable performance drop as of late too.

my suspicions are that my cat has collapsed and is blocking a lot of flow, but this is only a semi-educated guess. if someone could suggest likely/known causes, and ways to diagnose them that would be great.. fail getting an answer, ill be pulling my cat off at some point this week and bashing the crap out of it to see if that helps.

ta,
Damon

I have a TF, and i had a real bad rattle. I took off all the heat sheilds to see if it was them, no luck. I was about to take the cat off and bust the insides out then i thought what if i do it and it still makes the noise, so I took it to an exhaust place here in bendigo. They listened to it, knew exactly what it was.
Apparently there is a lil flappy thing inside the exhaust where the pipes join into one just before the cat. The guy reckons its common for 3rd gens for these flaps to get loose or fall off and sit in the exhaust. Mine had broken off and was sitting there. They fixed it for $50. No more rattle. I put it off for ages thinking it was the cat.

The furry bit with the tail...

:bowrofl:

nah, it's the boxy thing immediately behind the headers.. forward of the front seats


it's a bigger cylinder that the exhaust pipe?

it's a bigger cylinder that the exhaust pipe?

Yeppers

hrm, didnt think of pinging.. never really expected it.. but ill definently get it looked at tomorrow to be sure.

we chopped a hole in my muffler the other day and cleaned out the big chunks of rust, welded her back up and it still made the sound, cept more noticably now.. and you can literally pin point it to being below the driver seat, somewhere from the headers to the cat.

other issues is that my O2 sensor is currently dead, and reading 0.2v max.. ill be getting this replaced asap, but that should be making the can run very rich rather than leaning out shouldnt it?

ill get the car into the shop asap tomorrow and let you's know how i go anyway.

also ill be getting a whole new exhaust system asap so if it is something there, ill just dodge up a fix until the new one goes on :)

ta,
Damon

and you can literally pin point it to being below the driver seat, somewhere from the headers to the cat.

Could just be the plate in the factory exhaust manifold coming loose, but that really only rattles under load.. certainly won't make a noise when the car shuts off.


other issues is that my O2 sensor is currently dead, and reading 0.2v max.. ill be getting this replaced asap, but that should be making the can run very rich rather than leaning out shouldnt it?

Yeah, 0.2V is a lean indication which should make the car richen up in closed loop mode to compensate, but it's only just lean.. because of the way a narrow band sensor works it's very accurate around 14.7:1 so 0.2V is only around the 15:1 area.. which is probably not lean enough to cause you much grief if it's an accurate reading.

Good luck with it anyway :D

kk my mechanic said it isnt pinging, its either heat shield or exhaust so thats taken the pressure off!

im gonna pull apart my exhaust etc first chance i get in the next few days.. just needa know if ill need new gaskets, or will mani-seal be plenty to seal it up.

ta,
Damon

Probably is the splitter plate in the factory exhaust manifold then. It gets all metallic and rattly under load and under deceleration.. That's easy to fix.. get some extractors! :badgrin:

haha, wish i could afford extractors.. atm the current mission is to get a TermLab first thing in january :)