Fuel Filter on 2002 ML 320
 

Can anyone tell me where the fuel filter is on a 2002 ml 320? In addition, do you need to buy a modification kit when changing the fuel filter? Thanks so much.

It's hose clamped on the left side frame rail near the LR wheel...it can be a pain in the ass to replace, and if it has never been done, you will probably need to install the updated lines(3) due to the fact that the new fuel filter is longer than the old one.

The 163 and 230 are probably the worst fuel filters to do.

Hi,

does anybody have pictures of the layout for the fuel filter on the ml350

2002 MB ML320 fuel filter
 

You have to check your production date for your ML320. I thinks yours has the upgraded set-up an may not need any new lines. When you shop filters online they will give the production numbers to help determine if yours has the upgraded set-up. I think it does. If so you would only need the filter. The old style/pre-upgrade replacement filter is no longer available so anyone having the old style filter will be buying the new lines. They are sold/listed where you buy your filter online.

There are special pliers that remove the style of fastener used for the filter connections. I needed them because I had a botched job on my upgraded filter mandated by MB on some 2001's. "Someone" had managed to do the upgrade without using one the factory recommended upgrade lines. It made it nearly impossible to remove the line without destroying a line that cost over $100. Pliers range in price from $55 (mine) to $98 shop around.

You can disable your truck doing this upgrade. If a connector breaks or a line is damaged you won't be able to get something out of the "scrounge box" that will fix the truck. Back online.

General procedure:

lift truck
remove the left rear wheel
remove the wheel well liner
unplug the connector attached to frame (your looking right at it)
loosen hose clamp holding the filter
relieve the pressure in the injection system (or prepare for a gas bath)
you have the upgraded fuel filter/fuel pressure regulator ready to install
take note of the different connectors and locations
use your special pliers to remove the connectors (catch some gas)
install new filter (connectors snap onto filter)
put everything back where you found it
buy clean gas and you should be good for 100,000 miles or so

This job requires some experience to avoid some potentially deadly outcomes. As I said above if you break your connectors the replacements will shock your pocketbook. Deadly outcomes? On fire going down the road. Blow up and burn to death in your garage. An unexpected $250 bill for new feed and return lines if they are damaged. :hammer:

My first filter must have been changed early in the trucks history. It was mandated by MB that they were to be changed at the first opportunity. The filter I took off had 150,000 miles on it!! It seemed to run 'alright' before the swap but after the filter change there was a slight performance gain and better idle. It's rare to have anything really 'change' after a filter change unless it's really plugged.

Hope this helps.

Thanks Cybermechanic for your post -
Does your instruction work with 2004 ML350 ?

-Remove rear seat
-lift out carpet
-you'll see access cover (round) behind driver's seat
-remove access cover (round) takes flathead scrwedriver to remove old seal
-make sure you have updated 3 lines (updated lines just allows your fuel guage needle to show completly full)
-don't worry about using special pliers, just get some good dikes and cut the old fuel line. Becareful not to break the white fuel fitting!
-reinstall the new lines in the same way as old
-replace fuel filter
-flatten out the access cover and use good silicone to cover the hole

I most 2002 ML's have the new larger filter already and the correct fuel lines. Trying to use the retrofit fuel lines designed for the earlier small filter will not work.
If you cut the filter fuel line going to the engine, as suggested above, you are screwed.

When just changing the filter it is not necessary to remove the rear seat. The filter change is done from the left rear wheel well.

To satisfy any reservations you may have I suggest checking your VIN number with your dealer to make sure you need/don't need the filter upgrade.
Mike

[EDIT] --------SEE NEXT POST ----------

More Fuel Filter Information ------
 

I found an old 2009 post I made on another forum on this subject.

******************************************
The early ML’s built from 1998 to somewhere around March or April of 2001 had the original Fuel Filter PN 163 477 02 01. This was upgraded (for production vehicles and replacment service parts) to a new larger filter after March April 2001 to PN 163 477 05 01. Vehicles built after this time frame have the Larger filter. All these filters had a fuel Pressure regulator built in. Some of the first larger upgrade filters PN 163 477 05 01 had regulators that made a loud screeching noise and a newer upgrade filter PN 163 477 07 01 was put into the supply chain.

163 477 02 01 Short Filter
163 477 05 01 Long Filter (possibly noisy regulator)
163 477 07 01 Long Filter – Current Filter as far as I know.

Mike