fuel filter servicing

pinaster

Active member
Joined
Feb 27, 2005
Location
ITALY
TDI
caddy life DSG 1.9 PD
first time for me, during annual maintenance i found a very dirty fuel filter canister.

As you can see, after filter removal, there is a lot of black gunk.
Usually i change the filter and clean the holder every two years or 30K Km.

The car recently run poor and no really power pushing down the gas pedal.

Should I be worried for a dirty fuel tank too?

 

MyAvocation

Top Post Dawg
Joined
Jun 9, 2004
Location
Hoffman Estates, IL
TDI
2017 Passat SEL TSI
That's an unusual amount of debris, but I would not worry. Your filter is doing it job.

If still no power after new filter, then wait until tank is near empty, remove fuel sender from the tank and clean the strainer. Once in there you'll see whether tank should also be cleaned.
 

pinaster

Active member
Joined
Feb 27, 2005
Location
ITALY
TDI
caddy life DSG 1.9 PD
i'm planning to check again fuel filter and canister whitin few months, because on my car only solution to get access to fuel sender is detach fuel tank completely from below.

any idea why so many debris and where could come from?
thank you for taking time to answer
 

turbobrick240

Top Post Dawg
Joined
Nov 18, 2014
Location
maine
TDI
2011 vw golf tdi(gone to greener pastures), 2001 ford f250 powerstroke
It either came from the fuel station, or some decaying fuel hoses I'd say.
 

pinaster

Active member
Joined
Feb 27, 2005
Location
ITALY
TDI
caddy life DSG 1.9 PD
after filter change, almost empty tank, i put new fresh diesel and the car seems run much better: more power and no shaking engine at WOT.

let's hope it's only a random bad service station refuelling!
Do you think i need any additive to clean the sistem?

i'm also worried for my webasto thermo top, which come without fuel filter
 

MyAvocation

Top Post Dawg
Joined
Jun 9, 2004
Location
Hoffman Estates, IL
TDI
2017 Passat SEL TSI
No need to clean the system, filter served its purpose.

EDIT: By the way, what's that green ring around the top of the canister? Hopefully an optical illusion and not slime or film (organic matter).
 
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Ol'Rattler

Top Post Dawg
Joined
Jul 3, 2007
Location
PNA
TDI
2006 BRM Jetta
That's an unusual amount of debris, but I would not worry. Your filter is doing it job.

If still no power after new filter, then wait until tank is near empty, remove fuel sender from the tank and clean the strainer. Once in there you'll see whether tank should also be cleaned.
Yup..........

i'm planning to check again fuel filter and canister whitin few months, because on my car only solution to get access to fuel sender is detach fuel tank completely from below.

any idea why so many debris and where could come from?
thank you for taking time to answer

Look under your back seat, there is a small dinner plate sized cover for access to the lift pump/sending unit.

I would be inclined to pull the pump to see just how much crud there is in the tank although soot in the filter is somewhat normal on a BRM.

It comes in from the return from the injectors and IDNFS, but replacing the injector seals might slow down the soot migration.
 
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pinaster

Active member
Joined
Feb 27, 2005
Location
ITALY
TDI
caddy life DSG 1.9 PD
sorry no possibile to look under the rear seats: my car is a VW Caddy, different body from jetta or golf. In order to see the fuel sender you have to dismont the whole tank from below.

the green ring is only a reflection on the shiny canister.

i think that black debris could be algae, if you consider that here in EU is legal to sell diesel whit 4,5 up to 7 % of biodiesel blended.

anyway thank you for your interest, as soon as i check again fuel filter i'll post my findings.
 
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