FacelessZ

I plugged up the O2 bungs and am wanting to get rid of the SES light and delete out my O2's from the PCM. Will deleting out my O2's help my car run better?

Thanks!

OBE1 95Z28

You don't want to delete O2 sensors on a '95. These sensors are required by the computer to manage your air/fuel ratio during part throttle driving (99% of your driving). OBDII cars ('96 and up) have four O2 sensors; 2 before the cats and 2 after. The 2 before the cats manage the air/fuel ratio like on a '95 car. The 2 after the cats provide a self check of the cats (look at the O2 difference before and after the cat). A lot of guys delete the after cat O2's and replace them with O2 simulators to fake out the self test portion of the computer.

Injuneer

Appears you have a 1995. The 95 only has two "pre-cat" O2 sensors. These are critical to the air/fuel management system of the PCM. In effect, by deleting them, you have eliminated the ability of the PCM to operate in "closed loop", and eliminated the possibility of the PCM compensating for changes and mods that improve the engine's breathing efficiency. You will most likely experience reduced fuel mileage and increased emissions, since there is no longer a guarantee that the the engine idles and operates at part load at its most efficient A/F ratio (14.7:1). You might run lean enough to damage valves, or rich enough to start fouling plugs.

Unless you have a "race only" car, or you are using high levels of leaded fuel, there is really no advantage to eliminating the PCM's ability to operate in closed loop.

Just curious.... why would you try to delete the pre-cat O2's?

Josh-'04 GTO

That's a really bad idea. I think Fred explained it all, but essentially, the O2 sensors are the only real source of data as to how the PCM is doing in regards to air/fuel ratio.

FacelessZ

I just figured deleting them out would be the easiest...

Would getting two O2 simms help or should i actually get some O2's?

Injuneer

The "sims" are designed to simulate the output signal of the after-cat O2 sensors, which is not the same as the output signal for the pre-cat sensors. And sending "false" simulated O2 data to the PCM is just as bad, if not worse than sending it no data at all.

"Easiest" for what?

FacelessZ

Since you guys are the pros, what would you do in my shoes? I wasn't really looking for a breakdown of my short phrases, just some answers...

Thanks!

Josh-'04 GTO

You never told us what is actually wrong with your car....Your thread only asked how to delete the O2 sensors. Maybe if you could shed some light as to what is wrong with your car?

FacelessZ

Car is running in open loop cause all I did was block off the O2 bungs after my long tube install. Should I just buy a pair of O2's and extensions? Am I right in saying that Jason sells O2's for $35 a piece?

Would it even be worth it to buy new O2's or should I just stick with my stock ones...?

stereomandan

All you need are extensions.

Try the stock O2's. See how they work. If you get a code, then go from there.

Dan