DL31 - Check Vacuum Input to the EVR Solenoid

- Key "OFF".

- Disconnect source vacuum hose at EGR Vacuum Regulator (EVR) solenoid and connect hose to a vacuum gauge.

- Start the engine and let it idle while observing the vacuum gauge.

- Is vacuum above 15 inches at idle?

Yes -- Inspect vacuum hose from EVR Solenoid to EGR valve. If OK, replace EVR solenoid. Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)

No -- Replace the vacuum line connecting EVR solenoid to source vacuum. Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)