3501753 Oxygen Sensor for BOSCH fuel injection system. Has long connection wires. This sensor is installed by the catalytic convertor .
For the vehicles without turbocharger. 2 year warranty on the sensor.
Common issue with O2 sensor trouble code 2-1-2 preheat circuit caused by corrosion at the fuse panel terminal by the fuse #4
For Volvo 240 Years 1989-93,
Volvo 740 Years 1989-92,
Volvo 760 1987-90,
Volvo 780 Years 1987-90
Also Volvo 940 Year 1991

3517394 Oxygen Sensor
*Cars with Regina system.*
For Volvo 740 Years 1990-92,
Also Volvo 940 Years 1992-93,
Works for: Volvo 122 (1962 - 1968)
Works for: Volvo 740 (1985 - 1992), Volvo 940 (1991 - 1995)