Join Date: Sep 2000
Location: Shrewsbury, MA, USA
There,s probably 4 O2 sensors on your car, there is on my 96 4.3L Jimmy. 1 in each exhaust manifold, usually identified as bank 1 and bank 2 O2 sensor 1. Then there is one just before (bank 1 HO2 sensor 2), and one just after the cat (bank 1 HO2 Sensor 3). The only purpose of the last one is to monitor the efficiency of the cat. The ECM looks at the difference between the one infront of the cat, and the one behind the cat, and sets a code if the difference isn't greater than a set value.
It will eventually set the catalytic converter efficiency code. Does the car have about 100K on it? Thats about when my first cat went.
1969 Indy Pace Car
350/300HP RPO Z11
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.