My check engine light as been on for a while. Had codes read by a friend or a friend and I was told that the o2 sensor 2 bank 1 is reading 0 on my van. Does anyone know where it is located and how hard it is to change?

 

If your car has two EGO sensors, they should be on the part of the exhaust system while the pipes on both sides are still separated, such as on the manifolds or at the beginning of the Y or H pipe that they connect to. It usually has a large hex body, and requires a special socket that has a cut-out to get it past the wiring. However, I've found that if you can find the right sized box-end wrench, it will pass the connector through the opening so it can be used to remove/install the sensor. If the connector is too big, it is possible to disassemble it to pull the wires out so that you don't have to pass the whole connector body through the box end wrench. Make sure you note which wire went into which connector position.

Failing that, you can try using an adjustable wrench. If you strip the sensor body, since you're replacing it anyway, you can use a pipe wrench on it. Just be careful when installing the new sensor.

 

Okay, I will work on finding the right socket. Still trying to find out if anyone knows which of the two sensors it is. The code computer said sensor 2 bank 1. I have found the two sensors on the exhaust. Any ideas which one this would be, the front or the back one?

 

Checking the Chilton's manual electrical diagrams, the two sensors are on the same bank. (My Mustang has one on each bank.) However, it does not say which one is the front one and which is the rear one. I guess you can try to measure the voltages on them. On one of them, the wire to measure is grey with light blue, and the other one is red with light green. The reference on both of them is the grey with red wire.

 

Thanks for the information on the sensor. I will try and do the check as soon as it warms up.