Hi Warren,

It sounds like you’re talking about the sensor with the two vacuum lines running to it. It’s nearer the front top of the head. I’m not sure what the name is but I believe that what it does is allow gas tank fumes from the charcoal canister to be sucked into the intake once the engine reaches operating temperature. You’ll find a line that runs from the canister outlet on the left fender of the engine compartment. It goes down to what I call the throttle plate. I think its more EPA related then engine management, but if yours is broken there’s a vacuum leak.

Outofspec