Changing the engine intake or cabin air filter
Difficulty: 1/5
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Introduction

This article is divided into three sections: replacing the intake air filter, cleaning the snowscreen, and replacing the cabin air filter.  The snowscreen is the air intake snorkel which has a screen that keeps out large debris and snow out of the air intake box.  If it is clogged, then a spring loaded auxiliary intake flap opens preventing the engine from air starvation, but lets in warm engine bay air.

Parts

new air filters
phillips screwdriver

Procedure

Intake air filter replacement

All you have to do is unscrew the top cover.
(2 phillips screws).  Mine were rusty so I used a dremel to cut a groove in them and then used a standard screwdriver to remove the screws.  Just make sure the new air filter is seated properly at all the edges.

You can also remove the MAF electrical plug and unclamp the hose if you want. I also suggest vacuuming out the bottom of the air filter box and cleaning the snowscreen while you are in there.  Make sure the tabs all fit into their clamps and that the air filter edge gasket is seated properly.  Note that these cars are known for slow MAF failure.  If your car has been losing power, a faulty MAF may be responsible, see 1000q: limp mode for more details.  If you determine that the MAF is bad and need to remove the element, a special VW tool is required to remove the MAF screws.  You could also use the dremel to cut a groove into it and just replace them with normal screws.

Cleaning the snowscreen

Note that in the below pictures, the air box and battery were removed.

Remove (1x10mm) nut circled in yellow and pull out the intake snorkel.  The snowscreen is at the end.  Just use water or compressed air to clean it out and replace.  Note that there is also a spring loaded door downstream of the snowscreen.  This is to let bypass air into the airbox in case the snowscreen gets clogged.  The reason why this air is not as good is because the air from behind the headlight is cooler than the engine bay air that is drawn from the bypass.

Cabin air filter

Remove the 4 phillips screws (one is circled in red) and pull up and away the rubber weather stripping on top of the firewall.

Pull out the plastic trim and the cabin air filter.  Note for reassembly that the black plastic frame has 2 tabs on the top front edge, and 3 tabs on the lower rear edge.  1 of the tabs is marked in red.

Vacuum out any dust dirt from around the area and replace the filter and trim.  The ribbed cylindrical object below the air filter is the blower fan.

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