i just realized that my 89 iroc does not have the egr solenoid vacumm valve installed or the vacuum lines connected. the egr valve on the tpi manifold is connected electric and vacuum. what is the purpose of the solenoid valve. can i remove the entire egr system and do away with this system.

 

I too have a 89 IROC and recently experienced the motor struggles to start and wont stay running. Upon investigation, I noticed the back side of the EGR solenoid had an electrical plug disconnected (which I reconnected) but also there is a vacuum connection but no vacuum line insight? Question is where is the vacuum source to connect to (directly below the electrical plug) the solenoid?

Hoping for help