detroit99sts

Hi fellas here's what I got :

A month ago I bought a 01 z06 with bolt ons, halltech intake, Borla exhaust. Very clean and runs great. Couple weeks ago check engine light came on. Went to autozone and they ran the codes:

Code 1: P0430 (catalyst system low efficiency bank 2)
Code 2: P0430 (catalyst system low efficiency bank 2)
Code 3: P0133 HO2S-11

Car came with a hypertech tuner and predator tuner. But previous owner had a final tune done at a performance shop. I Tried changing O2 sensor but the car doesn't appear to have any. So, I'm not sure if I can just clear the codes with the provided tuners or do I have to visit a shop ? Not too sure where to start. Any advice is greatly appreciated.
-mike

enoniam

I'm very surprised that if a shop did the tune on an O2 sensor-less car that they didn't mask out those error codes. I'd take it to a shop/tuner as I don't think the handhelds can mask those out, and given that a shop didn't mask them out I think I'd want another shop to take a look at the tune.

detroit99sts

Thx for the advice. Yeah , so, the car drives great , very fast, but I'm wondering if someone can tell me whether or not it would drive better with clear codes.

enoniam

The first two would not affect how it drives. The last one I'm not sure about but I would guess it wouldn't either, given that if indeed you don't have O2 sensors it was tuned for Open Loop operation.

detroit99sts

Also when looking underneath I was only able to locate one welded bung. Is this normal , or could the other be out of sight ?

enoniam

Stock there would be 4 O2 sensors, one on each side of the 2 catalytic converters.

ApexerER

Yes but hose codes would be for the rear ones after the cats which the Tuner should have turned off if they are removed. Are you sure you don't have any O2 sensors at all?

detroit99sts

I will have to check again this weekend to see if there are any O2 sensors. It was a quick check. All I saw was a welded bung on one side, and nothing on other side. Tried feeling around and couldn't get too far , limited room. Will try again this weekend and post results. Thanks

detroit99sts

Ok so I finally got around to checking the exhaust, and yep, there is definitely 2 sensors before the cats, and 2 sensors after the cats. Note: this is an aftermarket system x-pipe with only 1 cat per side. Also, took her into autozone for a follow up and I got the following codes:
P0430 (same as first time)
P0430 (same as first time)
P1416 (different than first time) catalyst system low efficiency bank 2.

Not sure why the P0133 HO2S-11 code did not show up this time.

I'm not too educated with tech/tuning, so any suggestions are highly appreciated.....God bless !!

RonSSNova

You need to find a shop with hptuners or EFI live and have those codes just turned off.

or you can try replacing those sensors, then the cats if sensors don't fix it.

but way cheaper to just turn them off.