A restrictive, dirty air cleaner filter will cause a reduction in fuel economy and performance and an increase in emissions production and engine wear. The air filter element should be replaced according to the maintenance interval chart in this section, or more often in dusty conditions.REMOVAL & INSTALLATION
1990-93 Passat GL/CL Models
- Loosen the hose clamps to remove the rubber boot from the top of the air flow sensor.
- For ease of removal, loosen the clamp and remove the air duct from the air filter housing.
- Unsnap the cover retaining clips, starting with the hardest ones to reach. The last clip released will be difficult to unsnap, so it should be the easiest to reach.
- Lift the cover off and remove the air filter element. It's not necessary to disconnect any fuel lines or wires.
- Lift the fuel distributor/air flow sensor assembly enough to remove the filter element.
- With the paper side down, drop the element just a few inches repeatedly on a flat surface to shake out any loose dirt, then examine the element. On CIS-E equipped engines, there may be fuel stains on the element. Dry stains are not a problem, but if the element is wet with fuel, the fuel distributor could be leaking. describes how to pressure test the system.
- Wipe out the inside of the airbox and install the new element. Make sure the rubber seal fits properly into the groove in the lower portion of the airbox.
- Replace the cover and secure the clips, starting with the least accessible clip.
- When installing the boot on the CIS-E air flow sensor, make sure the boot is fully seated all the way around the lip before tightening the clamp.
The air cleaner element is located within the airbox, on the passenger side of the engine compartment. It is not necessary to disconnect any wiring or hoses from the airbox in order to remove the air cleaner element.
- Starting with the clip that is most difficult to reach, disengage all of the clips that secure the upper portion of the airbox to the lower portion.
- Lift the upper portion of the airbox, and remove the filter element. Be careful when lifting the upper portion of the element; excessive force may damage vacuum and electrical connections.
- Using a clean rag, wipe any accumulated dirt and dust from the inside of the lower portion of the airbox.
- On 1.8L Turbo engines, if necessary remove the screen in the lower air box and clean,
- Carefully install the new filter element into the lower portion of the airbox. Make sure to install it in the proper direction (open pleats face downward).
- Starting with the clip that is the most difficult to reach, secure the clips around the perimeter of the airbox.