Hi there.
I have a 2002 GTi 1.8T with 49k miles. About 4 weeks ago my check engine light came on and a diagnostic test revealed that my O2 sensor was bad. I was told that I didn't have to replace it right away, but should as soon as I could afford to. The part price was about $170. I decided to wait until after I'd moved. Three days ago, I got in the car and it wouldn't start. On the second try, after holding the key for about 20 seconds, the engine turned over and a small amount of black smoke was emitted from the back. I know the smoke could have just been build up from running on a bad O2 sensor for several weeks, but can this also effect the car starting up? Or would an ignition issue be a completely separate problem?
Also, I've ordered the part and plan to replace the sensor myself to avoid being over-charged by the dealer. Does anyone know of a good website that will have a diagram or manual that would help me out?
Thank you in advance to anyone who can help!