Replacing the Air Filter is part of VW TDI 20K maintenance. It needs to be replaced for one simple reason – your TDI needs clean air. And on turbocharged engines, air filtration is particularly important as debris can damage or destroy your turbo. The air filters on VW TDIs are scheduled for replacement every 20,000 miles.
Where is it?
The air filter is easy to find on the driver’s side of the engine compartment. There’s a snorkel system that takes air from the grill and routes it to the airbox.
The only tools you’ll need for the air filter element replacement is a Phillips head screwdriver and either a cable hose clamp release tool or a pair of water pump pliers.
Remove the airbox top
First, remove the hose that goes from the airbox to the turbo at the airbox end. Be sure to hold the airbox top as you remove the hose. The airbox anchors aren’t very strong and can break if you put too much pressure on them.
Once the hose is off, you can simply move it out of the way.
Then, loosen and remove the two screws that hold one side of the cover in place
Once the two screws out you can tip the back side of the filter cover up and remove the cover. The filter is hooked to the front of the base, but tilting it up will release it. You can unplug the MAF electrical connection if you want, but it’s not really necessary.
Once the cover is off, take out the filter element. This image shows what a dirty filter looks like. This one has 20K on it. Once the filter is out, wipe or vacuum out the base of the filter box.
After removing new filter from its box, press it into the filter base. The filter will be a tight fit, and almost seem too big for the box. The gasket is quite flexible and will press into place. The gasket is designed to seal only once, so resist the temptation to repeatedly remove it and press it back into place.
Once the filter is in the box base, hook the front clips on the filter top in their location and gently press the filter top into place. Fasten it with the two screws.
Reattach the intake hose and you’re done.
This is a simple and quick maintenance process that you can do in a few minutes. And then your TDI and its turbo are set for another 20,000 miles.