99 318Ti cabin air filter - where is it?

[mikeland]

My Girlfriends 199 318Ti is experiencing interior foggin during cold weather (up here in Canada). I suspect it is a clogged cabin air filter reducing ventilation. I took out the glove box and looked for the filter but no joy.

I did look at some E36 filter change postings but the ventilation system arrangement is different.

As an aside I did try the cabin recirc button which illuminates. I can't tell if the actual valave/flapper is working properly. This is a fogging similar to if the cabin air was on recirc. Side and rear windows fog heavily, front windshield can only be kept clear with defrost setting and fan on high.

I have checked for leaks/wet carpet but nothing there.

thanks for any asistance.

Mike L

[jmo69]

I think you're on the right track about the flapper. I had to have one changed on my 98 328is. I don't know if it's the same on your car but they said mine was a PITA and bought the whole duct and just swapped out the flapper. I think they said they used mirrors to see what they were doing.

[johnnyBgood]

There are 2 cabin filters, they are behind the the air plenum under the hood... On the Compacts...

johnny,

[mikeland]

Thanks for the info, I sense I'm getting warmer...

How do I get to the plenum.

I did remove the center grill between the wiper arms. This revealed 2 philips screws that released the plastic box below. This bow looked promising but only contained wiring harness (I popped 2 of the 6 retainer clips ope on the passenger side to reveal the harness).

I also removed the battery and box, revealing what i thought to be the cabin air inlet (wrong).

So anyway is there a diagram, exploded view, or tech posting that shows the plenum? Possibly a photo that even deals with another component that has the plenum visible will work.

cheers and thanks

[johnnyBgood]

Don't know why picture vanished from my prior post.....

johnny,

[johnnyBgood]

Just pull up weather strip, unclip grate.....remove screws from wiring harness.


johnny,

[mikeland]

Thanks so much

Man I had that secion apart today but did not look behind the plenum.

I assume filter removal is straight forward.

cheers

[johnnyBgood]

Originally Posted by mikeland

Thanks so much

Man I had that secion apart today but did not look behind the plenum.

I assume filter removal is straight forward.

cheers

No problem....Good luck....

johnny,

[96cali]

Mikeland- come on over to www.318ti.org - Home. We are an active, friendly group especially to DIYers like yourself. IIRC there is a writeup in the digest on how to change the cabin micro filters.

Hope to see you there!

Phil
96cali