Hello Folks, I just registered and I have a question, please. I have a 1999 Mustang, 6 cylinder and the diagnostic test said the problem of poor performance and the "service engine soon" light staying on is because of a faulty O2 sensor. Can I replace this myself in my driveway? Expensive? Help!

 

Where is the O2 sensor on my 1999 Mustang, six cylinder and can I replace it myself in the driveway? Is it expensive?

 

There are four O2 sensors and they are all located on the mid pipe. They are easy to take out, you just unscrew them. Helps if you have the special wrench for it. You can get new ones for like 20 bucks I think.

 

O2 sensors are about $45 each. Which one is out? An OBDII code reader will give you a specific code for it to tell you which one of the four is out..... there are two upstream and two downstream.