I drive a 97 LT1 Camaro and I got a Po400 code (EGR flow malfunction) So we clean out the EGR valve with carbeurator cleaner and we check to see if we are getting any vacuum to the solenoid and we arent. SO then we check the solenoid plug and we get a positive signal but no negative signal with the check light. So we triggered the Negative with a screwdriver and then we got vacuum. Does the PCM give it a negative signal when it is ready for the valve to open up? Or is there something wrong with the Negative electrical feed to the solenoid?

 

Yes, the PCM sends a ground to the solenoid to operate it.

 

So the negative terminal would not light up on a test light because the PCM hasnt triggered it yet is that correct?

 

Exactly.

 

alright cool, well shoebox you have been a great help in the past with your website and quickly responded when I had a thread with questions I just want to thank you for all of your advice and tech support I really do appreciate it.