Q7 4M 3.0 TDi Oil in the fuel filter.

[MaciejN]

Yesterday I changes my fuel filter at 83k Miles. Apparently was changed at 52k Miles by Audi service. When I removed the old filter I discovered that it is all black. I let it drain a bit and started to teaching it. In my opionon the black thing looks like an engine oil. Can someone advice if that is possible??

Short video how this filer looks like: https://www.veed.io/view/85e4c079-1723-44a8-b2bc-a2c3c757118a/showcase?sharingWidget=true 

Edited October 5, 2022 by MaciejN

[Autobarn]

On 10/5/2022 at 12:56 PM, MaciejN said:

Yesterday I changes my fuel filter at 83k Miles. Apparently was changed at 52k Miles by Audi service. When I removed the old filter I discovered that it is all black. I let it drain a bit and started to teaching it. In my opionon the black thing looks like an engine oil. Can someone advice if that is possible??

Short video how this filer looks like: https://www.veed.io/view/85e4c079-1723-44a8-b2bc-a2c3c757118a/showcase?sharingWidget=true 

Not possible, Diesel IS light oil so even if you pour something thick like 2 stroke oil in your tank it will dissipate into the fuel leaving no trace, more likely to be other unrefined products from forecourts sourcing cheep fuel during shortages, bitumen is just one of 6,000 products derived from crude but it is more likely to be an organic waxy product that I have come across on more than one occasion recently, not any concern as long as you keep on top of filter changes  

[Curtin88]

On 10/11/2022 at 10:03 PM, Autobarn said:

Not possible, Diesel IS light oil so even if you pour something thick like 2 stroke oil in your tank it will dissipate into the fuel leaving no trace, more likely to be other unrefined products from forecourts sourcing cheep fuel during shortages, bitumen is just one of 6,000 products derived from crude but it is more likely to be an organic waxy product that I have come across on more than one occasion recently, not any concern as long as you keep on top of filter changes  

Possible, injector seals will be leaking, allowing engine oil to contaminate with return fuel from injector back to fuel tank 

[Autobarn]

40 minutes ago, Curtin88 said:

Possible, injector seals will be leaking, allowing engine oil to contaminate with return fuel from injector back to fuel tank 

Injector seals sit between combustion area and atmosphere, there is no oil at the point that can be introduced, return pipe handles over fueling that has not even entered the injector, again no oil to be introduced ?