EWT

I replaced my air filter(s) tonight. As mentioned in several posts, replacement is more involved than the average air filter. All you need to do is lift the air filter housing up and off the top of the motor, but there isn't clearance without first removing several other things to make room. You'll need a 16 mm socket or wrench and E14 Torx socket to remove the strut tower brace, 10mm socket to remove 2 covers, and a T25 torx bit to disassemble the air filter housing. A rachetless socket drive came in useful as a couple of the 10 mm bolts on the covers don't have much clearance to swing a rachet.

Some pictures of the process. Ground zero:



First, lift the engine cover off the top of the motor (it just pops off), remove the inlet to the cabin air filter (to get clearance to remove the strut tower bolts) by popping the 2 clips with a screwdriver:



Remove 2 panels that form the "corners" of the panel in front of the firewall (3 10 mm bolts on the driver's side and 2 on the passenger's) and remove the strut tower brace:



The air filter housing can then be lifted off the motor after undoing a clip at the back of the housing and pulling the air inlets and a hose off the front of the housing :



The housing once it is off the motor:



Remove the 8 torx headed screws on the other side of the housing to get access to the filters inside. Installation is pretty much just the reverse of removal.

It really isn't that difficult, just a lot more work than replacing an air filter should be. It took ~35 minutes with hand tools stopping to take pictures along the way. FWIW, the Mann filters I put in were identical to the MB filters that came out other than the MB name and MB part number on the old filters - the old ones even had a Mann logo on them.

hubert

Is it the same on the diesel models?

Her350

The process is basically the same on the 350 Diesel. All of the same items do need to be removed to create clearance to remove the air filter housings. Visually, the only difference I can see from the photos is that the air inlet on the diesels are down low compared to the 450.

45 min process for the first time. The only hard to find tool was the torx socket.

lkchris

Air filter change on diesel models requires engine computer reset.

Fourdiesel

It does? Didn't seem to need a reset when I changed the air filters on my '08! Ran fine before, ran fine after.

lkchris

Doesn't change the fact WIS calls for it.

2010GL550

EWT - thanks so much for the photos and instructions. I successfully changed the air filter on our newly aquired 2010 GL550. Although I must confess I only ordered ONE K&N filter...duh. Waiting for the second one to arrive. Now I'll have a chance to do it all over again.

N_Jay

Does the vehicle tell you in the filter is clogged? (Maybe that is why?)

Wonder what the reset actually does?

2010GL550

I changed the filter(s) due to the Service C required message. Additionally, we just purchased the vechile with 20,000mi and I figured it was a safe-bet the original units were never replaced.

I'm under the impression Service C includes: air filters, cabin air filters, oil filter and oil change. Additionally there are several "inspection" items.

Once the oil change is done (tomorrow probably) I'll reset the Service C reminder as specified in this forum. Unless someone describes something else to me, that's all I plan to do!

alx

The diesel has pre and post air filter sensors. Resetting engine adaptations will result in setting a new baseline for air filter flow and efficiency based on which the next service c is calculated and requested.

If the engine adaptations are not reset any consequent service request will be skewed and most likely inaccurate.

N_Jay

Trying to understand this.


If you don't reset it, you might get a air filter needs replacing message at the wrong time?


Seems to me, as long as the filter is replaced before it was excessively clogged, I am not sure how this would happen?


Are air filters only needed with "Service C"? How often do they normally need to be replaced on the 320 CDI?
(Obviously the system will tell you when they are clogged, but what is the typical lifespan?)
(I have a coupon with Pelican Parts and are trying to figure out what to stock up on)

nataraki

sub'd.

melliott2005

I replaced my filters the other day and then started getting a CEL. Scanner says P0172 and P0175. Basically running rich. The isle is very rough, and it had cut off on one occasion in a drive thru.

I assumed i had the housing for the filters misaligned, so I disassembled everything again to start over. I am having trouble getting all four clips on the stubs. And the M clip at the back doesn't seem to lock in place no matter how much I fiddle with it.

I have done this several times with no issues. Had anyone else had similar trouble?

kombifan

alx

you are getting older and your fingers dont listen to you. operations that used to take 5 minutes now take 20 and your body hurts the next day. get used to it.

sorry. had to

bha

The reset is done through the instrument cluster. Can't remember how exactly, but there is a service menu and you can pick what service numbers were completed. If you pick the one for air filter, it resets that adaptation. I know instructions are out there because I google it every time I need to do it.

Think about it this way.. a new air filter and used air filter pass different amounts of air. The system adapts based on how old the air filter is. If you don't reset it, you can put a brand new air filter on and the system will think it is very old.

Best to reset it each air filter change. BMW's do the same thing in the 7 series batteries by the way..the computer is told that a new battery is installed, and charging of the battery is done differently (volts & amps are modified as presumably a new battery will charge faster and hold a larger charge... which then tapers off as it gets older either by mileage or time)

alx

air filter adaptations are not reset via the corresponding service.

also on bluetec setups with scr the air filter adaption reset does a urea heater descaling. it can be actually heard- there is a very audible gurgling in the **** tank once you hit the "reset" button in the star/ das tool.

lkchris

Yes, on stepdauughter's GL450. Just keep fighting it until it all settles into place. It was a PIA.

Yup497

Nice ride. 2010 White GL550 here.

wowchad

Great info here, especially this tidbit ^^ - thanks!
I'll be doing mine along with cabin air filter and oil/filter change for the first time on my 2014 GL350 this weekend as long as all my parts show up on time. They're coming to my shop via UPS vs USPS so I should be in pretty good shape.

TxRzrBk

deleted

Sallad

^^
wrong post buddy.