Just had our 2000 Classic V70 splutter and put up the check engine light - OBD reader says p130 (O2 sensor) reset the code and shes fine (for now !!) shes done 170,000 miles so probably due an O2 sensor - question is how many wires on the O2 sensor so I can order the correct one. many thanks, oh by the way, does anyone know how to wire past the overheat sensor on the aircon compressor? I think I may have this issue - ie no aircon but the system is full