Checking and adjusting the ignition timing are not a part of a normal maintenance schedule. The 2.0L Passat engines use distributors. Because the ignition system is controlled by the Engine Control Module (ECM) the only adjustment possible is the base ignition timing on the 2.0L 9A (16 valve) engine, which only needs to be set if the distributor, removed, disturbed or the timing belt replaced.
To set the base ignition timing on the 2.0L 9A engine:
- Start the engine and allow it to reach normal operating temperature. The engine cooling fan should cycle at least one time with the air conditioner turned off.
- Turn the engine OFF .
- Locate the timing access hole on the top of the transmission bell housing, and if installed, remove the protective cover.
- Loosen the distributor mounting fasteners just enough to allow the distributor to move.
- Connect an ignition timing light following the tool manufacturer's directions.
- Start the engine and check the ignition timing at idle. Note: The engine idle speed is not adjustable and is controlled by the ECM. If the engine idle is not within specification, trouble shoot the cause and repair as necessary. The timing should be 5-7° Before Top Dead Center (BTDC).
- Adjust the timing as necessary.
- Turn the engine OFF .
- Tighten the distributor mounting fasteners to 88.5 inch lbs. (10 Nm).
- Recheck the ignition timing and if necessary, adjust to specification.
Although diesel fuel and water do not readily mix, fuel does tend to entrap moisture from the air each time it is moved from one container to another. Eventually every diesel fuel system collects enough water to become a potential hazard. Fortunately, when it's allowed to settle out, the water will always drop to the bottom of the tank or filter housing. Some diesel fuel filters are equipped with a water drain; a bolt or petcock at the bottom of the housing.
Most 1990-92 diesel engine-equipped vehicles are equipped with a water separator, located in front of the fuel tank under the right side of the vehicle. The water seperator's purpose is to allow water to settle from the fuel right at the tank and to alert the driver when draining is required. When the water level in the separator reaches a certain point, a sensor turns on the glow plug indicator light on the dashboard, causing it to blink continuously. With the introduction of the A3 platform, the water separator was eliminated, and removing water from the fuel system is accomplished with a drain screw on the bottom of the fuel filter.
Checking and adjusting the ignition timing are not a part of a normal maintenance schedule. The ignition system contains few moving parts, and does not require any type of adjustments to compensate for wear. Unless the timing belt has been changed, or the distributor has been removed from the engine, adjustment of the timing is not necessary. For more information on the ignition system, refer to Section 2.