Passat Sedan 4Motion V6-2.8L (ATQ) (2003)
Variable Induction System: Testing and Inspection
Intake manifold change-over, checking
This test should only be performed if there is a loss of power.
The intake manifold switches from the long intake path to the short one at approx. 4700 RPM.
Special tools and equipment
-
V.A.G 1551 Scan Tool (or VAG 1552 mobile scan tool) with VAG 1551/3 cable
-
VAG 1526 multimeter or VAG 1715 multimeter
-
VAG 1594 connector test kit
-
VAG 1390 Hand Vacuum Pump
Functional Test
-
Start engine and let run at idle.
-
Increase engine speed clearly above 4700 RPM. This process should actuate vacuum diaphragm for intake manifold change-over. (Component
location: on intake manifold front left, beneath ignition coils).
If the change-over does not occur, the following tests should be performed.
-
Test activation of intake manifold change-over valve -N156- through the output Diagnostic Test Mode (DTM). See: Computers and Control
Systems/Testing and Inspection/Scan Tool Testing and Procedures/Output Diagnostic Test Mode (DTM) (Function 03)
If the activation appears to be in order:
-
Connect Scan Tool (ST) or vehicle system tester.
-
Disconnect vacuum hose (1) from check-valve (2) and connect hand vacuum pump VAG 1390 to disconnected hose.