Someone help me out here please I removed my lower o2 and i can't get my CEL to go off. I've tried to go the o2 simulator way but it seems the ecu is too smart for that. If the o2 readings stay at one point for over a minute the ecu sends a code. So i don't know what to do. On the flip side my gas mileage is not so bad. Don't know exactly how to measure it though, Maybe someone here can enlighten me on that too.

first off, miles/gallon = gas mileage. Fill up the gas tank all the way. Set the trip meter to zero before you leave the gas station. The next time you fill up, take the milage on the trip meter and divide it by the amount of gas you put back in to fill the car up again.

As for the 02 simulator where did you buy it from. because the point of simulating is to act like the 02 sensor is really there I'd try PM'ing velcita paola and see if you can't pick one up from him.

An alternative to using a simulator would be to try using the sensor as normal, but with a potentiometer spliced into the signal.

A potentiometer can be bought at any electronics store for fairly cheap, and it functions like a volume knob. Turn one way you get more resistance, the other you get less. Obviously you would still be using an oscillating O2 signal, and just use the potentiometer to decrease the average voltage of the sensor's feedback signal. Thus making the ECU think the exhaust has decreased O2 levels even without a catalytic convertor. The only issues are that you need an O2 bung welded in your exhaust, a good sensor and a protected location to mount the potentiometer. Then just fire it up and decrease the signal voltage a little at a time until you get rid of the "no cat" CEL.

BigRand said:

first off, miles/gallon = gas mileage. Fill up the gas tank all the way. Set the trip meter to zero before you leave the gas station. The next time you fill up, take the milage on the trip meter and divide it by the amount of gas you put back in to fill the car up again.

As for the 02 simulator where did you buy it from. because the point of simulating is to act like the 02 sensor is really there I'd try PM'ing velcita paola and see if you can't pick one up from him.

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I'll fill her up and post the numbers so you guys can tell me hows my mileage. This would be with the a/c on and occasionally flooring it ok

On the o2 simulator thing I actually made one from reading an old thread around here, but i guess it was intended for the 4g63 engine.

delta448 I'm trying to avoid having to weld on a 02 bung and wiring my o2 sensor back but thanks anyway.

A faulty downstream o2 sensor reading will not effect your fuel economy, and its not really a concern seeing as you have a test pipe installed. I had a downstream o2 code for a year and I run a test pipe. The day after I ordered an o2 simulator from Paul the code went off and has not came on again in over a year and i run a test pipe still. Fuel economy is still the same. If its the CEL that bugs you, talk to paul. he stands behind his products. I'm still not certain why mine decided to go off and never come back, but im not complaining. I do know the CEl still works btw, Got a TPS code right now cause of a crappy connection in the harness. I can jiggle the wires to get the CEl off . Need to do something about that.

I have the same thing with my car, sometimes the light comes on and other times it goes off. The CEL doesnt really bother me though. I remember one time i drop to New York and it was off through out the whole trip and when I got around my cousin's house the light came on and then went off like a week later.

So basically the CEL code for the lower o2 is not going to hurt my performance or mileage. Then this is not a major issue. Right? Guess I'll focus on other stuff first then I'll get around to fixing this. Thanks guys!