I have a 1991 2.05 honda prelude with ABS no 4WS. I think my VSS (speed sensor) is gone. The speedometer won't work. The car is idling up and down and trying to run hot most recently. Also, the check engine light is on. Do you guys think its the VSS, and if so, How do I locate it. I'd like to fix it myself.

 

You say the idle is up and down once it warms up, check your IAC valve

 

Actually it idles up and down from the start.

 

Run the codes and post what it says