91 525i E34 Cabin Air Filter

[zedtech2000]

Hey, I have a 1991 525i (E34), and I cannot find the cabin air filter! I have taken out pretty much the whole right side of the car in the cabin, and I cannot find it anywere. I saw a photo tutorial of an E34 M5, but there is no little slot next to the 'shark.' To my understanding it should be in between the 'shark' (I guess the AC Control unit) and the AC coils (if it is there, how do I get to it?) If anyone has any thoughts please help me! Thanks AZ

[Javier]

You have to take out the glovebox, the plastic trimming above it, the A/C duct that is fixed with screws in the wall behind the glovebox, and finally, between the black plastic cap covering the evaporator and the inner side of the firewall is a white plastic cover fixed by a small torx screw and a turning knob. Remove this white cover and you will find the Microfilter. Just let know if this helped you find it, as I can post more detailed instructions if you need them.

[zedtech2000]

Thanks, I will try this in the morning and tell you if it worked! AZ

[Dan in NZ]

Not sure when they started, but mines a 1990 and doesn't have one. I suspect 91 might have been the year they were introduced, but you'd have to look it up.

[Muratti]

quiet hard to do it yourself. They just keep the interior out of dust... (I think)

[632 Regal]

on my car it took about 50 minutes(being careful and studying how it goes together), the second time took less than 15 minutes. It's not actually that hard of a job.

[gcbbmw]

Some owners leave it out since the replacement job is
quiet hard to do it yourself. They just keep the interior out of dust... (I think)


leaving the filter off does not mean dust and debris will NOT came in! they will came in as usual but will slam against the heater core.

replacing the filter is way easier :)

if you really don't want to replace either, replace the HEPA filter with those fake carbon meshes they sell for regular house airfilters. they will not trap dust (you will breath it), just the bigger stuff that could damage the core

[BennyM]

Check your car's manufacture date. It might have been built in 1990 and not have a cabin filter.

[gcbbmw]

just did my filter yesterday, the compartment was filled with leaves and small things.

[genphreak]

Yep, one has to vacuum it out with a spout fitting to clean that up. Beware dates and filters; different markets & models got different options at different times.

A rule of thumb is that around 1990-91 they added filters. The later ones had other changes as well, such as a blower motor resistor in there that will CATCH FIRE if a dry leaf is blown onto it, so NEVER choose to leave a filter out!

[gcbbmw]

I can even picture how the cube shaped one would catch fire if a dry leave fall inside the faraday cage with the wire type resistors... but the filter does not help in any way, because those are in front of the filter. always...

the "resistor" that sits behind the filter is the sword kind. i've never seen that one...