CT03911

Spent part of the day reading Cat questions. Entertaining.
I know my cats are either bad or going bad. If anyone can help me with one of the options below that would be great.

Anyone have a set of decent used OEM cats for sale?

Anyone selling a cat bypass setup?

Anyone used hi-flow 100/200 cell cats welded in AND O2 sensors w/o check lite?

Can anyone sell me new 200 cell cats?

Thanks.
Dennis

911SLOW

I think cats have extended warranty in the US 8years or something if they are gone, so no need to buy another set. (If not and want to put oem again I have one in as new condition with little klm)

Another (better) idea if you have to pay for the cats is to upgrade to either

200 cell cats = no check light

100 cell cats = maybe check light

catbypass = check light for sure (cargraphic fvd etc have those)

Check light is an easy fix either with a dme upgrade or with extensions on the O2 sens.


Also there is a possibility that your cats are fine but you 02 sensors are going bad. What's the code?
One bank or both banks?

CT03911

Here are the codes:

P0430 fault code 45 catalytic converter efficiency bank 2
P0420 fault code 40 catalytic converter efficiency bank 1

I am expecting issues if I try to warranty replace them. There always are unless you have a garage queen.

Thanks.

SH || NC

I don't think a dealer can turn you down for cats if you are within the federal DOT year and milegae window of 8/80k.

I ran a 200 cell X/cat pipe set up on my C4S and didn't have a single problem.

Cat bypass, you can use the 02 extenders which move the sensor out of the exhaust stream and should prevent any CELs, but I have not had any experience with them.

mooty

i have no cat, no CEL. but it's track use only , always WOT. i was told it's cruising speed that causes CEL?

85Gold

Read the Warranty the other day as I popped a check engine light for Cat on bank 2. Warranty states that you have to fail an EPA test in the state to get warranty replacement. Didn't indicate that a check engine light for bad Cat
would trigger replacement under warranty.


Peter

cfjan

CT uses OBD2 for state emission check.. so a check engine light would automatically fail the state inspection.. !

Leigh2

I ran cat bypass pipes on my 6GT3 with the O2 extenders. CEL would not come on at the track but would come on after street driving. Easily reset with Durametric and the sound was great!

cfjan

So the CEL would still come on w/ the extenders?! That might not work for the state emission check then..

When the CEL is re-set via a OBD2 scanner, the readiness status would not be available and would be rejected by the emission check, I believe. (i.e., you can't just re-set it and show up to the emission check)

Leigh2

You're probably right I don't think the bypass is the way to go if emissions testing is required. It's not that hard to remove the cats and put on the bypass pipes and it can be done without removing the rear bumper. Keep the stock cats on for the test and swap them out for the rest of the year

996FLT6

^or know someone : ). I've been running catbypass with fabspeed muffs for 4 plus years with ^no cel(^no o2 extenders) but when initially ran catbypass with stock muffs cel would lite up on steady cruising. Weird. Mike

996FLT6

Leigh- when u coming down this season : ). My car should be ready by April : ). Mooty get use to seeing me behind u til the last lap in a race : ). Mike

cfjan

That's a good way to "save" your cat.. ha! So it is pretty easy to swap the cat in and out?!

Leigh2

Easier with the bumper off but I did do it with the bumper on once. Tight fitting the cats into place and the O2 sensors are a PITA to get in. If you're not in a rush take the rear bumper off...
Mike I'm doing the full season at Miller again but hope to make Spring Mountain in early March plus we'll be at LS in June; not sure I'll have my GT3 there as I think the truck is full so I'll probably borrow a ride. I'd like to do TH again as I didn't make it last year. It's on my bucket list to pass Mooty one day regardless of the cost...

964-C2

How many extra HP running a cat bypass (if any)?