E39 Cabin Filter Housing Procedure
The following information about the E39 Cabin Filter Housing Procedure is provided for reference purposes only and should be used at your own risk
In no event shall Beisan Systems, LLC or its members be liable for incidental, consequential, or special loss or damages of any kind however caused.
First, remove the left-side cabin filter housing and air duct. Next, remove the housing cover by prying the forward cover wire clip and pulling up on the cover from the front.
Then, disconnect the housing strut tower mount spring clip. After that, pry the air duct bracket off the filter housing using a flathead screwdriver and rotate the duct off the filter housing.
Once detached, pull the right side of the filter housing up and away from the front fender. Take note of the filter housing’s upper left rear frame positioning under and behind the cowl frame.
Finally, remove the air duct by turning it clockwise and pulling it out.
For left-hand drive cars, fill the sides of the DME box (located under the cabin filter housing) with cloth towels. This step is important as it prevents tools and parts from falling to the side of the box and becoming trapped underneath.
Cabin filter housing installation
Install left side cabin ventilation duct.
To begin, install the vent duct by rotating it clockwise from the installation position. Next, insert it into the firewall access, press it in, and turn the duct counterclockwise to hook onto the studs.
Note: For proper insertion, make sure to align the duct foam boot so it mates flush with the firewall opening (angled).
Note: If mounting is difficult, spray lubricant on firewall rubber boot (water based cleaner).
Mount cabin filter housing.
First, tilt the housing right side up and insert the housing air duct into the fender access hole. Then, position the housing’s rear left top frame behind the cowl frame for proper alignment. If needed, lift up on the cowl frame to ensure a better fit.
Next, place the windshield fluid hose, which runs along the fender, under the housing weather strip.
After that, fully insert the housing duct into the fender, align the housing’s rear slots with the cowl tabs, and lower the housing’s right side. Finally, insert the housing’s lower mount bracket onto the strut tower mounting stud.
Install filter housing strut tower mount spring clip.
Turn vent duct to mate with housing. Slide duct bracket bottom onto housing then snap duct bracket top three clips onto housing.
Install housing cover and snap on retaining wire clip.
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