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Home >> Volkswagen >> 1999 >> Golf (1W1) L4-2.0L (ABA) >> Repair and Diagnosis >> Powertrain Management >> Emission Control Systems >> Air Injection >> Testing and Inspection >> Pneumatic Valve, Checking
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Pneumatic Valve, Checking


Pneumatic valve, checking
Special tools, testers and auxiliary items
US 8026 hand vacuum pump

Test sequence
^ Disconnect vacuum hose from secondary air injection solenoid valve.
^ Attach US 8026 hand vacuum pump to vacuum hose.
^ Disconnect pressure line from pneumatic valve.

Note: Do not use compressed air for the following check.

^ Connect auxiliary hose to pneumatic valve and blow into it.
Pneumatic valve must be closed.
^ Operate hand vacuum pump.
Valve must open and operate smoothly (without sticking).
^ Replace valve if necessary.