eb02z06

iTrader: (18)

I turned off the rear 02's and cot on my 02 Z06 when i put my off road pipe on. however on the dyno I found the pipe to have no gain in power. So can i put my stock 02 pipe back on and run cats without having the rear 02's functioning and having the cot turnrd off? Thanks.

Predator

I don't think anyone knows for sure the effect of turning off COT with cats installed. I have cats with O2 codes and COT turned off, but I'm not worried about frying the cats as long as there are no other negative effects. I'd rather risk the cats to have my a/f not affected by COT dumping fuel.

wrencher

iTrader: (2)

I would think it is ok. The rear o2's just monitior catalyst performance. They do not influence fuel trim.OR .. Why not enable rear o2's?

eb02z06

iTrader: (18)

What does cot do?

Predator

COT (Catalytic Overtemp Protection) dumps fuel at PE/WOT if the cats reach a certain temperature, to cool them down and protect them; but the down side is that it skews your a/f ratio rich.

Lady Redhawk

iTrader: (6)

If you want to keep your cats, I would not disable COT it could melt them. You can adjust the temp that it kicks in would be better than not at all.

ChrisB

Yep, worst case you would melt your catalytic converters - you would know pretty quick if this happened (or at least you would know something is wrong) - your exhaust would get quiet, your car would have no power, and your headers would probably glow - if the car ran at all.

Now since the cat temperature is a calculated and not measured value there is some room here to work with - if you have longtube headers, etc. then you have moved your cats farther downstream - so they are probably already running cooler.

What it comes down to is the only way to know for sure is to try it... if you are still running stock manifolds then I doubt it will work, but with longtubes there is a possibility.