Volkswagen Cars 2000-05

Fuel Filter


Removal & Installation

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Fig. Diesel fuel filter detail

With diesel engines, absolute cleanliness is essential for the fuel system components. The injection pump of a diesel engine has extremely close tolerances; even small particles of dirt can seriously affect performance.

Changing the fuel filter on vehicles equipped with diesel engines is one of the most basic, yet critical forms of preventative maintenance. Replacement of the filter every 30,000 miles is recommended.

  1. Open the fuel filler cap to relieve any pressure that may be in the tank.
  3. Disconnect and plug the supply line and injection pump fuel lines from the filter.
  5. Remove the clip from the control valve (located on top of the filter), then remove the valve, leaving the two lines connected. Position the valve and the lines off to the side.

The control valve is delicate, so be careful during removal and installation.

  1. Loosen the mounting clamp nut/screw, then lift the filter assembly straight up. Discard the old filter.

To install:

  1. Install the new filter onto the mounting clamp. If there are arrows indicating fuel flow direction, they point towards the front of the vehicle. Tighten the mounting nut/screw until the filter is secure.
  3. Install new control valve O-ring seals (using fresh diesel fuel for lubrication) and install the control valve into the flange on the top of the filter. Secure the retaining clip.
  5. Connect the fuel lines to the filter. Use new clamps if they are damaged.
  7. Connect the negative battery cable, then start the engine. Accelerate the engine a few times (this will clear the air bubbles in the fuel system) and check for fuel leaks.
  9. Don't forget to tighten the fuel filler cap.