I just swapped out the throttle body on my car, not because I needed a new throttle body but because the IAC valve I needed was attached to the throttle body with 4 circle-headed philips screws that didn’t want to budge. Anyway, When I went to reinstall everything, I realized there was an extra electrical connection I hadn’t noticed before. I located the sensor it connected to on my old throttle body, removed it, but when I went to install it on the new throttle body I found that the position it was supposed to mount in was occupied by a much smaller allen bolt. This unkown sensor off the old throttle body was too large to fit in the threading of the new throttle body. I stood there staring at it for a few minutes, then said what the hay and just put her all back together again leaving that sensor disconnected. I turned the car on, and it fired right up and revved when I hit the gas. I haven’t tested it on the road yet as I had dropped insurance on the car for the summer and haven’t reinstated it yet.
My question: could anyone tell me exactly what this sensor is, what it does, and why I really do or don’t need to have it connected? (pics below)
From what I can infer, it is a very simple (single-pronged connection) sensor that reads whether the throttle is open or not. There is a “button” that rests on a plate and is depressed when the throttle is closed, and when the throttle opens it lifts the plate and the “button” on the sensor releases. The smaller allen screw on the new throttle body seems to operate as a limit stop, preventing the throttle from “over-closing” when in resting position. Moreover, every throttle body schematic I have been able to find depicts the allen bolt as is on the new throttle body, and I can’t find anything to help me along in my Haynes manual. The closest thing I can come up with is either a coolant temp sensor or intake air temp sensor, but neither of those makes sense to me given its position.
Any help would be much appreciated.