Tandem pump

[ajweekes]

Just changed the air and fuel filters on 56 2.0TDi 170 (after 3.5 years and 65K). My god what a difference forgot how quick it was!

Both filters were black. The air one I can understand, but I’m concerned by the fuel filter, it was jet black. I’m guessing this is the tamdem pump letting engine oil mix with the fuel?

This seems to be a common fault. Any idea on how much it costs to replace and if VW are likely to make a contribution?

[DSG4ME]

They go black anyway as they age, don't worry about it if the car runs nicely, if you drag the fuel filter out in say 5k time you will find it half and half in colour, the fact it's black means it's done it's job properly, the black you are seeing is sediment from petrol station tanks that unavoidably gets in the underground tank when the tanker driver opens it up to re-supply it, and all the little bits of muck that get on the fuel cap that then find their way into the tank. hth.

[ajweekes]

Should it be this black?

[DSG4ME]

Yep, shocking isn't it.

[gamichea]

Seem to remember the change schedule on my old B6 was very long both in time & distance. I asked my at my dealers about changing it earlier in view of the tandem pump issues which were common on here at the time and got the answer "its not a bad idea" so for peace of mind I had it done.

Do the CR engines have the same tandem pump arrangement anyone know?

[tommyweaves]

Should it be this black?

Depends where you live!

(P.S. I'm not a bigoted woman, it's a genuine reference to air quality in different parts of the country)

(P.P.S. I'm not a woman either)