Checking Solenoid Valves For Obstructions & Leaks Vacuum System

Vacuum System, Checking

Checking solenoid valves for obstructions and leaks
- Remove relevant intake manifold changeover valve.
- Disconnect connector from intake manifold change-over valve.
- Connect one of the contacts on the solenoid valve to engine Ground (GND) using test leads and alligator clamp from VAG1594 connector test kit.







- Connect the other contact on the solenoid valve to positive using remote control VAG1348/3A, adapter lead VAG348/3-2 and auxiliary cable.
- Operate remote control VAG1348/3A.
- By blowing into the connection, check whether the valve is opening properly.

If the valve does not open:
- Replace relevant intake manifold changeover valve.

If no malfunctions are found in the tests performed up to this point:
- Re-install the intake manifold change-over valve.
- Check vacuum system for leaks.

Checking vacuum system for leaks
- Disconnect vacuum hoses from relevant vacuum unit for intake manifold change-over system.
- Connect hand-held vacuum pump VAG1390 to vacuum unit.
- Operate hand-held vacuum pump and check whether change-over function is working.
- Test vacuum unit for leaks. (The vacuum unit should not return to the "rest" position while a vacuum is being maintained via the hand pump.)

If the vacuum unit returns to its "rest" position:
- Replace vacuum unit.

If the vacuum unit is airtight, check all vacuum hoses for leaks.