You can check to see if you are getting 12-13 volts to your oxygen sensor heating circuit from the passenger side footwell. Just remove the floormat, and then find the two white wires, leave them plugged in and just back probe them (you should be able to do so on the connector, just look for the metal leads)


from reading up on the forum i came across another oxygen sensor test that you could try. i'm not 100% sure if it applies to your car but, what the hell, its worth a shot.
try this to check what kind of output(voltage) you are receiving from your oxygen sensor output wire when it is disconnected from the ecu. to do so:
1. make sure the car is at operating temperature
2. do not disconnect the oxygen sensor heater circuit(2 white wires) because the oxygen sensor will not output a proper voltage unless it is at proper operating temperature.
3. you can then disconnect the oxygen sensor output wire from the ecu, and then hook up your positive lead from your digital volt meter to the O2 sensor output wire, and the negative lead from your voltmeter to ground(i use batt. neg terminal). this should give you an idea of how the engine is running without the computer . a low reading could be a vacuum leak , whereas a high voltage would probably indicate a problem with your fuel delivery.

good luck