CrazyJoker

This is bullshit. This morning I went to a local speedshop to install an Autometer air/fuel gauge and boost gauge along with a dual gauge pod. They weren't RX-7 specialists, but they were confident that they could do it without a problem. The install for the boost gauge went fine, but I was shocked when the guy told me that he couldn't connect the air/fuel gauge because my car didn't have an O2 sensor! The problem is that my other idiot mechanics who made a custom 2.5" downpipe for me and installed it a few months ago were too lazy to drill a hole and create a custom mount for the O2 sensor to go back in, they simply cut off the O2 sensor and just grounded the single black wire on the turbo! All these months I was running my car WITHOUT an O2 sensor and I never even knew it. I was so pissed when I heard this. Now I have to buy a new O2 sensor and get a hole made in the downpipe so that the O2 sensor can be mounted in it. Question is, how could my car have been running all this time without an O2 sensor? I previously thought that it wouldnt run without an O2 sensor, but now I think it would just make the car run like ****. It never really ran like **** but I did notice poor gas mileage and it didn't seem to pull that hard under boost. How could the car run properly all this time with no O2 sensor to read from? Any thoughts on this?

13BAce

When the wire broke on my O2 sensor a long time ago the car got bad gas milegage and it didn't pull like it always did. When I fixed it the car ran much better. When the ECU doesn't "see" the O2 sensor it just runs richer as a default safety measure.

13BAce

By the way, what shop did the downpipe? You can PM me with the name.

Scott 89t2

the O2 sensor will make no difference under boost as the ecu ignors it. but it will give slightly better gas millage and running while cruising. I've driven mine around for a few weeks with it unpluged and couldn't tell the difference.