Signs of a blocked cat

[VR_Acclaim]

Ok so my issue wasn't a cas I think I changed my coils leads an cam angle sensor.. Car runs really well but gets to 2300rpm and gets dulll but now revs threw it after 2 secs or so.. I was advised it could very well be a blocked cat what do u think

[bpefi]

Leave it till its cold (they get very hot at times) & hit it with a rubber hammer or your hand usually they will rattle if they are failing as the ceramic comb breaks up - other than that - pull it out & have a look as its good to know how good its condition is - usually there is only 2 bolts each end - use some sensor safe silicone to reseal it after wards.

[hako]

From my experience with blocked cats, it will rev to a certain speed and stay at that speed - it will not increase after a few seconds......then gradually over a few days the top revs will drop till it basically will only idle. Have you done a fault codes check?

[soop]

If the catalyst is moving around you can hear it through the exhaust. Sounds like someone putting a potato over the pipe on and off.

[karlos]

Does it meowww?

[soop]

LOL, did your teachers hate you at school?

Smart arse :P

[VR_Acclaim]

Done codes got nothin it run fine but gets to 2500 and gets Spey an then it works threw it which up
Untill the leads today it didn't maybe plugs?

[bpefi]

Would you like to repeat that so we can understand ??

[VR_Acclaim]

Sorry ok so yesterday it would rev to about 2700 and wouldn't go further just slaves..today I've replaced leads and coil...and it works threw the dead spot..yesterday it stalled and wouldn't idle or do anything.. It free revs in neutral...I was thinking maybe a fudged plug??

[hako]

Maybe have a look at the engine when you bring it up to the revs where it stalls at night during total darkness - this will show up any high voltage leakage from plugs/leads/coils....look for the blue sparks.
As a wildcard suggestion, try resetting the ECU by disconnecting the battery for 30 seconds....stranger things have been known to happen.

[GTP 85]

fuel pump maybe? or fuel filter??

[jetboy]

From my experience ,best an easiest way , an thats without pullin anything apart an gettin dirty etc etc . Is to get ur mate to give it a few darn good revs whilst u hold ur hand over the tailpipe , then look at your hand , if its got all goldie lookin specks all over it that twinkle in the sun . Your cats stuffed , give it a go . Personally , i took mine off knocked the guts clean out of it an threw the empty shell back on the car , looks the part but there aint nuthin in there .Gives a bit more grunt , prob not much but enough to peel the doors of a XR6

[jakstas]

inb4illegalrant

[Vee-ard]

The inside of the cat isnt enough of a restriction to slow even a V8 let alone a stock V6. knocking it out wont get you anything except a MASSIVE fine when the cop with the infra red gun points it at the cat and sees its too cold to have an inside. Its no faster at all.

People who knock out the guts out of cats are in the same category as people who cut springs.

[jetboy]

Ppppphhhhhhffffffttttttttttttt

[jetboy]

The inside of the cat isnt enough of a restriction to slow even a V8 let alone a stock V6. knocking it out wont get you anything except a MASSIVE fine when the cop with the infra red gun points it at the cat and sees its too cold to have an inside. Its no faster at all.

People who knock out the guts out of cats are in the same category as people who cut springs.

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Rito champ dyno ur car wuth the cat on , then dyno it with a "gutless" cat , see the results for urself > better still POST EM > prove me wrong................................

[D3V14NT]

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Rito champ dyno ur car wuth the cat on , then dyno it with a "gutless" cat , see the results for urself > better still POST EM > prove me wrong................................

Do you have dyno figures to show that gutting the cat DOES do anything? Works both ways.

Plus I've heard from a few places that gutting the cat gives the exhaust a crappy tinny noise.

[Krisp]

The inside of the cat isnt enough of a restriction to slow even a V8 let alone a stock V6. knocking it out wont get you anything except a MASSIVE fine when the cop with the infra red gun points it at the cat and sees its too cold to have an inside. Its no faster at all.

People who knock out the guts out of cats are in the same category as people who cut springs.

nothing wrong with cutting springs, knocking out cats or putting milo tins on the exhaust. its cool just like smoking menthols

[IMCRZY]

Ok so my issue wasn't a cas I think I changed my coils leads an cam angle sensor.. Car runs really well but gets to 2300rpm and gets dulll but now revs threw it after 2 secs or so.. I was advised it could very well be a blocked cat what do u think

Just undo the exhaust before the cat and rev it,

Revs as normal = Blocked exhaust

[VR_Acclaim]

I had an idea and my fiancé. Thinks the same could it be the box as it dragging threw the 3rd gear

[jetboy]

No crappy tinny noise here , matter a fact everyone comments on my "note"

[jokerflingo]

No crappy tinny noise here , matter a fact everyone comments on my "note"

Im sure the cops would too when they catch you :P

[jetboy]

Im a family man an drive sensibly , i dont go out cruizin the streets at night them days are over for me . I have'nt been pulled over in a good 8 years , an only been booked once in the past 16 yrs or so , had no gutts in the cat for a good 6 , an besides coppers up here in QLD arn't as anal about the pollution shit as their southern counter parts .

[Brett_jjj]

I live in the country,so maybe these catalytic converter tests happen less frequently up here,but Ive never even heard of anyone getting busted or fined or whatever for a non working catalytic converter.Ive heard some ridiculous things that people have been busted for,but never for a non working cat.Ive noticed whenever someone mentions anything about a gutted cat on here,people go on about how you will get this big fine etc etc,if it were as common as any other defect,surely we would hear about it more often,even in the country.They dont even check the cats operation at rego time.Also if its replaced when the exhaust system is replaced,you should never have trouble with it getting blocked,unless you hit something on the road that smashes the catalyst inside it.I know theres a lot of young blokes around here who have gutted their cat believing it goes better or sounds better whatever,Ive been in a few of these cars and there seems to be very little gain,if any, in performance over the same car with a working cat installed.It doesnt even seem to change the sound that much really either.I dont run a gutted cat.

[D3V14NT]

They don't get checked very frequently. They sometimes check them when they do the big roadside roadworthy testing operations and they sometimes ask people they pull over to come in on blah day to get it checked. Usually you'll only get asked to have it checked out if you're a twat to the cop or they have good reason to think you've damaged/gutted/whatevered them.

Fines can vary greatly. Lack of or improperly functioning cats make the car unroadworthy which can leave you open to fines from the police, which is a few hundred or so depending where you live. However if the fine comes from the EPA from the emissions laws the fine can be several thousand. All depends who's doing the testing/fining and how much they like/dislike you.