If it is a 1990 or 1991 3.6L it has one 02 three wire sensor very easy to get at and do between the two cats in the open or buy a universal kit and splice one on for half the price. It is a must have to get ride of the engine pulses the v8's commonaly have when driving. If it is a 1992-94 4.2 I'm almost sure they have two 02 sensors. I have 3.6
