Omega de cat

[Leonwhite]

Hello was just wondering is it ok to de cat a v6 omega will it throw up and any engine lights or is there any sensors to worry about

[Doctor Gollum]

I would be more concerned about it passing inspection without...

But to answer your question, yes it will put the EML on and it won't run right as the ECU needs the O2 sensors to regulate fuelling. You might get away with it if you fit the sensors to the decatted pipe but the emissions will still be off.

[Leonwhite]

Thanks it is for a track car so not worried about inspection so u think put the sensors in the de cat pipe may work

[TheBoy]

Which V6?

[Leonwhite]

2.6

[Jan Suhr]

You need both sensors and the one that is after the cat will throw error codes.

I don't know if it is possible to cancel the 2nd sensors from the ECU with a TechII, but if it is you need to do that to not give the errors.

[Enceladus]

If the O2 sensors are throwing errors doesn't the ECU limit the engine to 4k rpm? Not desirable on a track car.

On the 2.6/3.2 each bank has a pre-cat and a main cat. The downstream O2 sensor is in-between the two, unless it's been modded. Therefore I imagine that you could remove the main cats, leave the pre-cats and the ECU would be unaffected, whatever about actual emmisions measured at the tailpipe?

[TheBoy]

I don't know if it is possible to cancel the 2nd sensors from the ECU with a TechII

Its not.

[TheBoy]

2.6

So doesn't have to be road legal?  The ECU will not adjust its paramters just because there are 0420 and 0430 codes (cat inefficiency codes).

There are 2 cats per side, a "starting cat", also known as a pre cat, and the main cat.  On the 2.6/3.2 these are cheap nasty things. 

[Raeturbo]

So how can we just do away with the four of the fuuuuing things and still run the car ok then?

[Kevin Wood]

So how can we just do away with the four of the fuuuuing things and still run the car ok then?

No, it needs the front sensors for closed loop mixture control.

If de-catting, best bet is to fit the sensors to the new pipe and ignore the P0420 / P0430 codes.

[Raeturbo]

Thanks👍