No problem. You can get a catted d/p and then you won't have to reflash your PCM. Check this link: ZZ Performance and then scroll half way down the page. Feel free to get a catted d/p anytime

 

Sorry to hear what you got hit with. Glad it's fixed, but I am certain they hit you hard for the price of that cat. I'm certain there are other options that could have saved you some money.

It's tough to make some of those decisions though once your car is in the shop. You are some times at the mercy of the people at the shop.

Hopefully no more problems (and if they are, hopefully they are CHEAP ones).

 

I put in the ZZP downpipe with Cat last year. No other changes. Runs great - throws no codes. Very happy customer.

 

Expensive lesson to learn and I should have known better. I could have bought the pipe at O'Reillys for $209 and was going to install it myself but two different repair places gave me the same sell. Both said the aftermarket pipes would have the check engine light on within a year. SOB

 

It is true that in most cases an aftermarket Cat will cause the P0420 code to come up, but that doesn't mean you can't put in a fake sensor that will prevent the code, or have the PCM delete the code from its memory (since all the rear 02 sensor does is monitor the cat it wouldn't harm your car)

 

This is reminding me of when I wanted to put the high flow CAT on my Monte. I never thought I'd mod the car enough to pay and get a tuned PCM (which would make the best sense to delete the code at that time).

At that time, I decided if the code popped I found that trick with spacing the O2 sensor out using spark plug anti-foulers. But, it never popped that code AND I've modded my car to where I needed the tune anyways.

@garshev - It's a lot of money, but unless you can take it back (and I doubt it), don't kick yourself over it. As I said, you were at the mercy of what you knew at the time and what the shop was telling you. I think ALL of us fell pray to that problem at one point or another. At least your car is running right again.

 

Very true, back in the day before I knew as much about W-Bodies and the shop said I needed to replace both front wheel hub assemblies and I lost $700, just to realize now it was probably just a dirty connector and never needed the work done.