De-cat but no 02 sensor?

[Mastiff 0]

When I bought my 96 VR6 last week the guy told me she has had her cat removed, he had this done when he had the s/s exhaust put on.

He gave me the original exhaust system......One thing I noticed on the original exhaust....It has an 02 sensor in there with a wire coming out of it. Question is, will my car be running ok without an 02 sensor as she does stink a bit of petrol when first started. Also de-catting a VR6, good gains or not worth it?

Thanks in advance.

[DrRich 1]

As long as ALL the other components are working correctly (MAF, coolant and intake temp sensors, camshaft position sensor, spark plugs, injectors, throttle body position sensor) then your mixture will be pretty close to perfect and there'll be no problems. Any sensor fault could cause trouble without you knowing it. Also, there'll be no way for the engine to account for the ravages of time (bore or piston ring wear, ageing injectors or plugs, etc) so that may throw the mixture off a little.

So, as long as you think the rest of the engine is OK, you'll be fine and should pass emissions at the MOT / roadside check...

In the longer run, I'd think the O2 sensor would be sensible to look after your engine's health. You can get a sensor bung cheaply in many places and any good garage should be able to weld it in.

Running rich at start up is OK as long as it clears quickly and runs smoothly when warm.

I don't know about gains - have heard top end power better at the cost of a little torque at low end, but no proof of this.