Help with 2zz O2 sensors

[mattbrown82]

Hi,
I've recently bought an MR2 with a 2zz conversion and it has a MWR manifold, decat pipe and a stock exhaust. I'd like to fit a cat for the MOT but I just need a little help with the o2 sensors.

I have bought a standard MR2 cat and my plan was to get a second o2 socket welded onto it before the cat.  I would then fit 2 bungs in the MWR manifold.

Can anyone confirm that if I just extend the O2 cable which currently connects to the right side of the MWR manifold so that it reaches the newly welded socket on my cat it will run correctly without any CEL's?

Many Thanks
Matt

[steve-m-uk]

Assuming your 2zz is running a stock 2zz ecu then you should only have two O2 sensors, one before the cat but after the point where all four runners come together ( this is important or your air/fuel ratio will be way off ), and one after the cat. In your case i would fit bungs to the manifold and have an O2 boss welded into the pipe just before your cat, you can either extend the wires on a short O2 sensor or use a spare after cat sensor which will have a longer wire.

[mattbrown82]

Yes I'm on a stock celica ecu, so I'll get a post cat sensor and plug it in the new socket before the cat.

Thanks steve  s:D s:D