this o2 sensor is known as a nerst o2 sensor and uses a different concept of reading the o2. it uses a pumping cell in the sensor to pump o2 into a chamber and compares it to the cars exhaust.DO NOT try to instal a 2 wire conventional o2 sensor you will have more problems and mil lghts on. these cars had several problems such as the vaccum suction pump plugging up with carbon. it sits ubder the intake manifold(not fun to cahnge). also if the turbo boost valve leaks you could have vaccum leaks.It sits at the top left side of the engine with a vaccum hose to hit. check with vaccum gauge. also checkfor any other vaccum leaks. I changed many of these o2 sensors due to 'sporadic no response' codes. Are you sure it has 5 wires ? a conventional one will have 4 ,2 for the heater circuit and 2 for the sensor. the nerst one uses 6 wires.