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Changed my 80k miles original fuel filter about 2 yrs ago and was saving it in case anything else went bad (float, etc). But given all the injector failures figured I'd dissect it to see what can go wrong.

As previously known the filter has an integrated pressure regulator. The regulator is located on the bottom of the unit, on the 'clean' side of the filter (i.e. it regulates gas after the filtering media). If media gets clogged up it will not prevent media from tearing and sending junk downstream to the injectors. Honestly I don't think locating the regulator on the inlet side of media would make much difference. If media gets clogged then there will still be a major pressure difference across it even if the inlet pressure is limited by the regulator. But I'm digressing here. The regulator itself is a simple diaphragm and preloaded spring. The rubber was not cracked or damaged on my unit, except for some dirt accumulated on the diaphragm. It's also been speculated that the pressure regulator can fail shut causing injector failure. I can't think how this design can fail shut except if the bottom 2 inches or so in the tank are full of dirt to the point where the spring and diaphragm are blocked by dirt... The filter would get clogged before this ever happens tho.

The filter itself is standard pleated paper-type with glued plastic end caps. An oring on each cap seal the filter element against the top of the housing (outlet) and against the bottom of the unit where the regulator lives as well as the connections across the tank. I was surprised by how much the orings were elongated. Assuming either fail then oring pieces and unfiltered gas will be supplied to the engine.

On to pics... dirt accumulated in 70-80k, nothing unusual. Notice how loose the cartridge orings look.
Wood Beige Soil Serveware Landscape



Notice the main outlet and pressure regulator outlet (regulator removed) are lined up in the pic.
Watch Wood Clock Automotive lighting Circle



Filter media has done its job. Notice clean interior.
Automotive tire Wood Asphalt Sand Auto part


Pressure regulator diaphragm showing some sediment - nothing sticky tho.
Hand Automotive tire Finger Wrist Auto part



Not much else to say other than change your filter if you've never done it!
 

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Interesting, thanks for the pics. Have been thinking of doing mine, have to assume it's the original. Flipside is that the car doesn't seem to have any fueling issues, but it's definitely on the list for the near future.
 

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Is there part number for just the filter? All I could find is the fuel pump assembly.
 

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I’ve got 51k miles and have been planning on doing mine here in the next few months. I’m backlogged on car projects at the moment, time to take a few days off from work and get to it.


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Agree with Flaco, replace the filter before it stresses out the fuel pump and then you are forced to replace both.
 

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Changed my 80k miles original fuel filter about 2 yrs ago and was saving it in case anything else went bad (float, etc). But given all the injector failures figured I'd dissect it to see what can go wrong.

As previously known the filter has an integrated pressure regulator. The regulator is located on the bottom of the unit, on the 'clean' side of the filter (i.e. it regulates gas after the filtering media). If media gets clogged up it will not prevent media from tearing and sending junk downstream to the injectors. Honestly I don't think locating the regulator on the inlet side of media would make much difference. If media gets clogged then there will still be a major pressure difference across it even if the inlet pressure is limited by the regulator. But I'm digressing here. The regulator itself is a simple diaphragm and preloaded spring. The rubber was not cracked or damaged on my unit, except for some dirt accumulated on the diaphragm. It's also been speculated that the pressure regulator can fail shut causing injector failure. I can't think how this design can fail shut except if the bottom 2 inches or so in the tank are full of dirt to the point where the spring and diaphragm are blocked by dirt... The filter would get clogged before this ever happens tho.

The filter itself is standard pleated paper-type with glued plastic end caps. An oring on each cap seal the filter element against the top of the housing (outlet) and against the bottom of the unit where the regulator lives as well as the connections across the tank. I was surprised by how much the orings were elongated. Assuming either fail then oring pieces and unfiltered gas will be supplied to the engine.

On to pics... dirt accumulated in 70-80k, nothing unusual. Notice how loose the cartridge orings look.
View attachment 954198


Notice the main outlet and pressure regulator outlet (regulator removed) are lined up in the pic.
View attachment 954199


Filter media has done its job. Notice clean interior.
View attachment 954200

Pressure regulator diaphragm showing some sediment - nothing sticky tho.
View attachment 954201


Not much else to say other than change your filter if you've never done it!
Flaco what is your take on using a fuel system cleaner / injector cleaner from a reputable company/bmw? (additive type)
 

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2008 E60 M5 Dinan S2+
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AWesome. Thank you @flacoramos! BTW, you need hand moisturizer. LMAO 🤣 🤣
 

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2009 BMW E63 M6, Sapphire Black
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Very interesting, thanks for the write up. I changed my E60 and E63 filters, and both were clean as a whistle, no dirt. The filters were dark, but no dirt like you show. maybe it fell out, when I used a sledge hammer to open it, but I don't think so. I still have both filters sitting on workbench, to see if the M6 filter changed colors over time, since it was pretty fresh at the time of these photos. 37K mile fuel filter -vs- 85K mile fuel filter
 
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