Need help.....again

[JBerryhill]

There is a plate mounted on the passenger side of the throttle body on my 87 GMC 350. It has mutiple parts attached to it but the one in question has a 2 prong plug on the top, a vacuum port on the front and two on the rear. The top most port on the rear on mine only has a 1 1/2 inch piece of rubber tubing on it. Should something be plugged into this port or is it a vacuum relief port? I will include a pic. Thanks Guys....

[frogman68]

the hose next to it does it go to the Egr ? if so nothing goes on that one thats what it looks like to me 

[VileZambonie]

That's the solenoid filter vent

[JBerryhill]

Thanks everyone, I really appreciate the help. This is my first TBI truck and I'm trying to run down a little stumble it has. So far I have found 2 cracked vacuum lines and a burnt hard plastic line. I found the one mentioned in the earlier post and just wondered if a line was missing from it.  Thanks again, Jerry

[78 Chevyrado]

That's the solenoid filter vent

yeppers.