Well about 6 months ago my 1990 Maxima SE went through about 3 months of complete crappiness. The Y pipe after 12 years in Chicago weather was crapping out on me along with the o2 sensor. I believe that this was the cause for a bad idle and shaking. So I got my warpspeed y-pipe and o2 sensor and put it in. Still had idle problem. So I check the computer and it comes up with knock sensor problem and I also checked injectors and 2 and 3 are bad again. I have fixed the injectors and the car runs better then I ever remember.(dad was origional owner) Will the knock sensor make that much of a difference? Becuase currently even with both Chiltons and Haynes manuals I cannot figure where the thing is underneath the manifold on the car. Any pictures or advice for me would be helpful.

Is there supposed to be a wire hooked to this or what. The book says to bring it to the dealer but being that I am 17 and broke after buying the 2 injectors,y-pipe, and knock sensor I really don't want to pay 250 dollars for them to do something which seems simple.

 

If you replaced your y-pipe, you can replace your knock sensor. I dunno how hard it is to take off the manifold on a VG but it should be pretty straightforward. You'll definitely see it when you take it off. It's a smaller round sensor with wires coming from it, plugged directly into the top of the block. Figure $130ish for the sensor and $40 for gaskets, etc. I'm just pulling these numbers out of my butt though since I have a VE. It's easy to do, just don't drop the new one!

 

not to doubt what you are saying but I from the pictures in my books it says that it is underneath the rear exhaust manifold not in the valley like in VE's (wishes he had one)

 

someone has to have replaced it on a VG