Federal 2WD, All Calif. Carbureted Vehicles & All Fuel Injected Vehicles

Remove connector from solenoid valve. Measure resistance between solenoid valve terminal leads. Specified resistance is 32.7-29.9 ohms. If measurement is out of range, replace solenoid valve.
If resistance measurement in step 1) is okay, measure resistance between solenoid valve terminal leads and body ground. Specified resistance is 1000 ohms or more. If measurement is out of range, replace solenoid valve.
Check vacuum passage for opening and closing operation while applying electric current on both positive and negative terminals. If solenoid valve does not operate properly, replace with a new one. If solenoid operates properly through all tests, valve is normal.