Im throwing my header on right now, and will drive it to the exhaust shop to have the rest of the exhaust welded up, and an o2 bung installed. how will it run and drive without the sensor plugged in?

 

iirc the car doesn't use the O2 sensor until 5th gear... correct me if i'm wrong

 

you're wrong...

it just wont run in closed loop, so it'll be rich in the 1200-3500rpm range. should drive fine

 

ok.. thanks i've been wondering about that for a hella long time. kept on reading that almost everywhere...

 

You won't even notice the difference

 

Tanjo I am in seoul we should linked up I have my RX7 here in Korea

 

so is it bad in general to run without an O2 sensor for a long period of time?

 

Just hurts fuel economy, so little change is noticed that many don't even realize it has failed. First generation fuel injection.

 

so u save more gas with it working properly?

 

Yes, because the system can lean the gas mixture out better as its getting feedback from the exhaust stream regarding the amount of excess oxygen which correlates very closely to how much extra fuel is being injected into the combustion chamber.

 

I second that. If the computer senses something is wrong, it will just run in closed-loop mode. This will lower performance and fuel economy, but really does not do anything bad to the car.
I had a VW removed the egr valve. The O2 sensor measured the difference in flow with the egr on or off, so it was throwing a code since the egr never opened. There was a simple mod to place a variable resistor inline with the O2 sensor--fixed the problem. Driveability was much improved afterward.

 

with it, it'll run 14.7:1 without its like 12... running 12 just to go a constant speed is a waste of fuel