The SES light came on and would go away and then came back again. It's been started happening a couple of weeks ago and my mechanic said the outer read-out was that there might be something wrong with the o2 sensor. He said he would need to remove the supercharger to replace it, so that's like at least a grand worth of work. Really?

 

I know of two o2 sensors and both are on the exhaust header. Would not need to remove the supercharger. One of the NAM vendors has a good write-up on the o2 sensors, see below.

Also going to move you to the Stock Problems/Issues area.

http://www.pelicanparts.com/techarti...eplacement.htm

 

What about the knock sensor? The computer also listed that. I'm guessing that one is accessed from the bottom too and there's no need to remove the supercharger?

 

Yes, you have to remove the supercharger to replace the knock sensor. With that off if makes sense to change the water pump if it has not been replaced in the past 70k miles.