3500 upper? iac or wat

[gar70614]

on my 3500 upper next to the throttle body there is a tear drop shaped place with one hole with machine threads and a larger holethat conects to the neck of the mani> wat bolts there? is it something that had to do with the fly by wire or is it something else. there wasnt anything there wen i got the motor so need to know wat goes there or if i should just plug it. thanx

[CNCguy]

The charcoal cannister purge valve was located there. You can plug it or use it for a vacuum source.

[IsaacHayes]

Yup evap purge solenoid. IAC is controlled directly with the electronic TB. Cruise, IAC, and throttle all in one with the electronic TB. 1/4" NPT tap if you want to use a vacuum barb...