Ok code 43 is fuels supply or O2 code.
Which O2 sensor have you replaced?
Does the car have any oil leaks?
Does the car drive abnormal? hesitate, buck, etc.
I have seen where the engine is leaking oil. That oil makes its way into the connector for the front O2 sensor. Since the O2 is located in the pipe at teh rear of the motor, slightly under the oil filter. When the oil gets into the connector it causes the readings to become out of whack and the PCM sets a code for it.
So there was oil inside the connector?
Was the problem gone when you put the O2 in a few months back?
So once you replace the O2 and cleaned it it didnt even last through its first drive?
This is reminds me exactly the problem i had. I replaced the O2 sensor 3 times but the car was ok for a few weeks. Finally i had to replace teh engine harness. Once the oil gets inside you can never get it out.
you can always try to make a piece of harness and bypass the section that goes down under the intake to the sensor. Essentially taking the oil soaked part of the harness out of the picture. If the problem is gone than you know for sure its the harness.
The connector by the O2 is connector c105. There is another spot by the right strut tower where connector C210 is. that connector houses the same wires as C105. You can try to back the pins out of c210 and run new wires down to the O2 ans see what happens.