Beetle L4-1.9L DSL Turbo (ALH) (1998)
Diesel Intake Air Shut-Off Valve: Testing and Inspection
With Generic Scan Tool
Change-over Valve For Intake Manifold Flap, Checking
Recommended special tools and equipment
-
VAG1390 Hand Vacuum Pump
-
VAG1526 multimeter or VAG1715 multimeter
-
VAG1594 connector test kit
-
Wiring diagram
Test requirements
-
The respective fuses of Diesel-Direct fuel injection system must be OK:
-
Battery voltage must be at least 11.5 Volts.
Checking function
-
Start engine, and let run at idle.
-
Switch ignition off.
-
Observe position lever on change-over valve for intake manifold flap (2nd technician required).
-
Intake manifold flap must close after ignition is switched off and open again after approx. 3 seconds.
If the change-over does not occur, the following tests must be performed.
-
Check whether the change-over mechanism of intake manifold flap moves easily. To do this, operate the linkage by hand.
-
Disconnect vacuum hose from vacuum actuator -1-.
-
Connect V.A.G 1390 hand vacuum pump to vacuum actuator.
-
Operate hand vacuum pump and check the change-over mechanism for the intake manifold flap for ease of movement and function.
-
Check whether the vacuum lines are correctly connected.
If no malfunction is detected at mechanical components:
-
Check change-over valve for intake manifold flap.
Test sequence
-
Disconnect connector from change-over valve for intake manifold flap.