DirtyBalt09

iTrader: (2)

So I noticed alot of ppl having issues with Cat effciency codes on modded or catless downpipes. What about if your car is stock I recently purchased my 09 SS and a week later Im getting PO420 and they are wanting to replace my cat. Would this be pretty common to replace the cat or is there something they might be missing. And will this truely fix the issue at hand. Eventually I plan on getting a tune but at this point I was gonna wait it out a bit before modding.

rukkee

iTrader: (3)

I'm assuming you bought it used so .....have you looked under the car to see if it has the stock downpipe? There is a chance that the prior owner swapped it for an aftermarket downpipe. I haven't seen or heard about many SS/TC's having downpipe issues ..... In fact, you would be the 1st one ive heard of having a bad one.

black08ss

ya i've never heard of a bad cat stock? unless the previous owner ran race gas for some stupid reason which might burn up the cat and throw an ineff. code

mccullj

iTrader: (2)

that exact code just came on on my 08 TC....i just installed a catless DP over the weekend.

DirtyBalt09

iTrader: (2)

To be honest I havent seen the underside of it yet. I got it over the weekend and havent had time to really get it up on a lift yet. Likely going to be happening Tuesday or Wednesday since my service appointment is scheduled for Thursday . It would be nice to have a "free" downpipe. Im just hoping if they do replace the cat they are not going to just cut and weld and would replace the whole pipe. I bought the car certified used so i was assuming there where no mods to speak of as the car doesnt even have an after market airfilter. I do have my suspicions though as sometimes I'll boost up 21lbs + in 2nd and 3rd which from what Ive read is much over stock in the midwest region in summer temps. I guess ill know more later this week.

Also any tips in general about how I would be able to identify an aftermarket pipe?
They didn't say the cat was missing just that it had to be replaced. due to low effciency

rukkee

iTrader: (3)

They will replace the whole pipe I'm sure . There are two big cat's and an o2 bung that im sure they wont want to cut and weld both back in.

DirtyBalt09

iTrader: (2)

Putting car up on lift today . Ill grab som pics and post them from what I've see on the ground it looks like a stock pipe. Previous owner may hve gutted the cats or something crazy or had an after market pipe and now that its not there its setting the code? I think the car may or may not be tuned already which makes me wonder can you set PO420 with a tune and stock pipe? Id guess no since P0420 has to do woth post catalyst readings anyways . Maybe tune is running to rich or lean?
Either way pics of pipe and car coming tonight.