Engine Compartment/Exhaust System

Fig. 35 Oxygen Sensor Locations:

Federal Emissions Package
Two sensors are used. The upstream sensor (1/1) is located just before the main catalytic convertor. The downstream sensor (1/2) is located just after the main catalytic convertor.

California Emissions Package
4 sensors are used. The front/upper upstream sensor (1/1) is located in the exhaust down-pipe just before the front mini-catalytic convertor. The rear/upper upstream sensor (2/1) is located in the exhaust downpipe just before the rear mini-catalytic convertor. The front/lower downstream sensor (1/2) is located in the exhaust downpipe just after the front mini-catalytic convertor, and before the main catalytic convertor. The rear/lower downstream sensor (2/2) is located in the exhaust downpipe just after the rear mini-catalytic convertor, and before the main catalytic convertor.