You dont mention the year of your vehicle. I will explain the procedure for a W210 chassis.
The fuel filter is adjacent to the fuel pump located on the drives side in front of the rear axle. There is a plastic cover held with (3) 10mm nuts that must be removed to access these parts. See the related link below for a step by step explanation with pictures on how to change the fuel filter.
How to change cabin air filter Mercedes E320
To the best of my knowledge, as an owner of the E class, the filter and the sending unit are contained IN THE FUEL TANK; hence the reason for the $300.00+ charge to change it...
The fuel filter on my 1999 E320 is located on the drivers side just in front of the rear tire. There is a plastic cover with 3 plastic nuts; remove those and you will see the filter. DominicArnold@cox.net
underneath the drive side passage seat in fuel tank...
Replace the filter It is never a bad idea to replace a fuel filter if the problem still persists you need to look elsewhere for the problem.
Somewhere between the fuel tank and the engine. Get under the car and follow the fuel lines.
To change the cabin filter on a e320 Mercedes the glove box needs to be removed. Once removed the cabin filter will be easily accessible. Then replace the unit.
replace cabin filter E320 2007
I have a clk 320, and mine is under the car, near the rear diff, on the passenger side. You cant miss it, and its eay to change. The fuel pump is right next to the fuel filter. I'm assuming your 2003 is in the same location as my 2002. Good luck.
Change the fuel filter first. If that doesn't help, change the fuel pump.
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