Doing maintenaince on the beater truck and...

[Snatch Napkin]

I came across a sensor on the passenger side of the intake manifold that has a 90 degree rubber fitting that looks like it had a vacuum line going to it, but I see nothing else out of place.

The vehicle is a 1997 Chevrolet 1500 2wd vortec 350/ automatic.

The sensor in question is in front of the coil (in relation to engine layout from standing directly in front) and right next to the throttle body.


Is this fitting supposed to have a vacuum line to it or not? The dust buildup inside it says it has been open for years.

The truck idles and runs great.

[Snatch Napkin]

This sensor has two vacuum ports. One goes to the evap canister.

I would figure this other one goes to the intake, but I don't see anything missing.