I need your help!
I think the cat died today, but i really dont know so HOW DO YOU KNOW IF THE CAT HAD DIED?
(And of course i mean the car cat!)

I started hearing what sounded like somethin vibrating underneath the car, and then their was this major power loss (thats right silencr, thats why u beat me :P ) the passenger also claims he heard some 'popping like noises'.

So, what do you guys think?

Well the power loss would be consistent with a failed cat....I was driving a suzuki baleno once and it was running like an absolute pig, no extra noise though and the internals of the cat had collapsed, simple fix, took the cat off, knocked the remaining innards out of it and put it back on....worked a treat LOL lol

I need your help!
I think the cat died today, but i really dont know so HOW DO YOU KNOW IF THE CAT HAD DIED?
(And of course i mean the car cat!)

I started hearing what sounded like somethin vibrating underneath the car, and then their was this major power loss (thats right silencr, thats why u beat me :P ) the passenger also claims he heard some 'popping like noises'.

So, what do you guys think?Best way is to get under the car and tap the cat with your hand, if you can hear the inards rattling around then you know it is stuffed.

And for those who want to know what a cat looks like on the inside, its like a honeycombe, and eventualy it can break up, many things can cause it.

Cats' can also die due to age, like jake said the interior is hundreds of ceramic flywire style meshes one after the other, as they collect particular exhaust emissions(their intended purpose) they basically get filled up allowing near to zero air flow. So if you or any of the people you know are mechanically minded pull it out(should be 4 bolts, 2 either side and maybe a mounting bracket) and have a look through it, should be perfectly symmetrical diamonds all the way through, if you cant see light or it looks crumbly it's buggered :)

Matthius

i was sad when i read the title!

[QUOTE=Matthius] "like jake said the interior is hundreds of ceramic flywire style meshes one after the other, as they collect particular exhaust emissions(their intended purpose) they basically get filled up allowing near to zero air flow.' " :cry: Is made from magnesium & cost bout $400 up(8 yrs ago) .Also holes will never fill up or blocked with ****. Actually catalic converter will dissolve and evaporate with time & then you can hear this rattling.

[QUOTE=Matthius] "like jake said the interior is hundreds of ceramic flywire style meshes one after the other, as they collect particular exhaust emissions(their intended purpose) they basically get filled up allowing near to zero air flow.' " :cry: Is made from magnesium & cost bout $400 up(8 yrs ago) .Also holes will never fill up or blocked with ****. Actually catalic converter will dissolve and evaporate with time & then you can hear this rattling.
A cat can block up if you use leaded fuel, not that anyone here is stupid enough to do that or can still get it.
And it can block up if you have a missfire, as the unburnt fuel goin into it is no good.

It also can kill a car running entirely (I'm 2 for 2 cats...)

[QUOTE=Matthius] "like jake said the interior is hundreds of ceramic flywire style meshes one after the other, as they collect particular exhaust emissions(their intended purpose) they basically get filled up allowing near to zero air flow.' " :cry: Is made from magnesium & cost bout $400 up(8 yrs ago) .Also holes will never fill up or blocked with ****. Actually catalic converter will dissolve and evaporate with time & then you can hear this rattling.

The meshes are a ceramic compound and yes they will get blocked over time, exhaust emissions leave residue, look at the back wall of a dyno room, this is like a powder and blocks cats, it all depends on how it's driven, a magna thats thrashed will regularly dip into the 10/1 AFR which will leave excessive amounts off soot on the cat. It's the same effect that "settles" a muffler as the residue collects in the fibreglass packing.

Matthius

Thanks for the replies.
So the 'symptons' i described in the first post sound like its the cat then?

Thanks for the replies.
So the 'symptons' i described in the first post sound like its the cat then?
I should of asked this first, can you now hear a exhaust rattle when revving the car, if you can that is very consistent with a blown cat, still best thing to do is to hit the cat from underneath and see if it rattles like something is loose inside.

I should of asked this first, can you now hear a exhaust rattle when revving the car, if you can that is very consistent with a blown cat, still best thing to do is to hit the cat from underneath and see if it rattles like something is loose inside.


Yes, i am finding that...

I should of asked this first, can you now hear a exhaust rattle when revving the car, if you can that is very consistent with a blown cat, still best thing to do is to hit the cat from underneath and see if it rattles like something is loose inside.

thats an affirmative
/looks for nodding head smiley

lets hope it is and is only the cat. :confused:

Not too difficult to remove and conduct a visual inspection, as described here.
Mitsu sells new std cats (bolt on) for less than 200. They generally last about 3-5 yrs and 100-150 G km.

I have a groaning/loud exhaust noise just around 2800rpm. Gets very loud when accelerating to say 100k's in 3rd where the car is doing round those rpm's. Sounds like it is comming from under the drivers seat.

Was wondering if that is likely to be the cat. Is there any other mufflers other than the rear one and the cat?(wagon) If not, im guessing it might be the cat. Car still feels fine with no power changes though.

Also, how would you check to make sure your oxy sensor etc are working ok?

I have a groaning/loud exhaust noise just around 2800rpm. Gets very loud when accelerating to say 100k's in 3rd where the car is doing round those rpm's. Sounds like it is comming from under the drivers seat.

Was wondering if that is likely to be the cat. Is there any other mufflers other than the rear one and the cat?(wagon) If not, im guessing it might be the cat. Car still feels fine with no power changes though.

Also, how would you check to make sure your oxy sensor etc are working ok?

Form headers back, first is the cat, then a longish resonator, then a short resonator and then finally the all-killing-muffler. So, only one mufler out of 4 cans in the pipe.

I think u need ECU diagnostic tools or good volt meter and the proper instructions from a repair book to check Oxy sensor. Minor differences in the voltage makes it work inefficiently. I have never tested mine tho.

Thanks Killer.

Probably a stupid question. Do the resonators usually **** them selves? How would i tell what is making the droaning noise?

Thanks Killer.

Probably a stupid question. Do the resonators usually **** them selves? How would i tell what is making the droaning noise?

You're welcome.
Wwoahh - quite difficult to say without hearing this. If the overall noise of the exhaust is quite similar to original (new std pipes and cans) but u have some vibrating, rumbling sounds at certains revs, but not too loud, then I'd guess a resonator/s is/are busted. But - saying that, resonators are quite small in size and their ability to "muffle" is not much.
Busted cat would make more rattling noise if the guts are shattered and bangning about. Totally cleaned off cat wouldn't make any more noise IMO.
It is typical for Magna exhaust to have this resonating at around 2000 and then close to 3000 etc and it's very audiable if the muffler it self is dud.
Hope this helps.