How do you test a egr switching solenoid? I’m getting a code po401 ( exhaust gas recirculation flow insufficient) on my 03 Sable dohc. The egr valve itself is fine and functions properly under vacuum. I’m wondering how to check the solenoid
I would apply 12 volts and ground to the pins. If you hear it click its probably functioning. You could also apply vaccum to one of the ports before applying 12 volts and see if it holds. Then apply the voltage to the pins while holding vaccum and if it releases vacuum its letting air through which also indicates it is working.