Operation CHARM: Car repair manuals for everyone.

With Generic Scan Tool



Combination Valves For Secondary Air Injection (AIR) System, Checking Function And For Proper Seal

Recommended special tools and equipment







- VAG1390 Hand Vacuum Pump

Test requirements:
- No leaks in vacuum lines or hose connections.
- Vacuum lines not clogged.

Test sequence







- Remove engine cover (arrows).







- Remove the air intake tube (arrows) between the air filter and the throttle valve part.







- Remove coolant reservoir -3- (arrows)
- Disconnect wire from Engine Coolant Level (ECL) Warning Switch - F66- and lay coolant reservoir to side.

NOTE: Coolant hoses-1- and -2- remain connected.







- Disconnect vacuum hose -1- of combination valve to be checked -2-.

NOTE: Left valve is displayed in illustration.

- Connect e.g.. V.A.G 1390 hand vacuum pump to vacuum connection of combination valve to be checked.







- Loosen mounting parts -1- to -4- and remove noise insulation.







- Disconnect pressure hose -1- at Secondary Air Injection (AIR) pump motor and blow air in with light pressure (do not use pressurized air).

NOTE: Disregard items -1- and -2- as well as arrows.

- Both combination valves must be closed, it must not be possible to blow through hose

- Operate hand vacuum pump.
- The respective combination valve must open, it must be possible to blow through

If the respective combination valve does not open:
- Replace the combination valve.

Final procedures
After repair work, the following work steps must be performed in the mentioned sequence:
1 - Check DTC memory "Mode 3: Check DTC memory". Diagnostic Mode 3: Check DTC Memory
2 - If necessary, erase DTC memory "Mode 4: Reset/erase diagnostic data". Diagnostic Mode 4: Reset/Erase Diagnostic Data
3 - Generate readiness code. Readiness Code, Generating

- End diagnosis and switch ignition off.