the fuel supply code 43 is set and has 3 different diagnostic trees, two of which lead to replace o2 sensor.

at the dealer when a car comes in with a 43, it's an automatic start with heated o2 sensor. hook up the multimeter, run the engine at 3000 rpm, and watch the voltage. if it's switching between .1V - .9V too slowly, it's loosing it's touch. replace it. never use an o2 sensor not designed for your car, especially an OBDII lambda sensor in an OBDI engine.


lambda sensor is bad