steveinwis

98.5 A4 1.8T Q. Check engine light came on few months back. Dealer tells me it is the O2 sensor. Wants $375 to do it. Is this a possible DIY and can anyone point me in the correct direction. what happens if I let it go? Thanks this board rocks.

Yippers®

You can either buy replacement parts (OEM is Bosch).. plug and play or buy a generic Bosch sensor and splice it in. Folks report mixed success with splicing Bosch sensors onto the OEM electrical connector.
If you are going to swap one, I'd buy a O2 sensor socket . .save you some hassle.
If the rear sensor is gunny and is the source of teh MIL you don't have to change it as that is merely a tattletale sensor. The front sensor aids in adjusting fuel mixture and if it is this sensor that has failed, it should be changed forthwith.

rgc36537

I recently replaced the stock o2 sensor on my '00 1.8T with VW o2 sensor (part # 06A-906-262-Q). It looks identical to the stock sensor and even has the same connector. The only difference I could see was that the harness was about 7 inches shorter than stock. After adding some length to the harness, it was plug and play. So far, the sensor has been in for a week (approx 400 miles of driving) and there are no signs of problems.

The VW sensor was $22 at my local VW dealership.

whatzinaname

https://forums.audiworld.com/vag/msgs/456.phtml

®ob

Do NOT splice. I repeat, do NOT splice