• Evo Magazine are looking for a mint and (and ideally unmodified) Leon Cupra Sub8 to drive and photograph for a feature. Find out more here .
  • Hey Guest👍👎 We're looking for reviews of your local CUPRA or SEAT Dealership - it's quick and easy to do: Leave a review now
Previous owner might have slung some used engine oil in the tank at some point?

Otherwise it's the tandem fuel pump seal thats failed.
 
As above my mk2 was the same an old VW mech gone solo at a local garage told me there all the same was told it was caused by blow by on the injector seals and if its running ok leave it. 60000 miles later its still the same and running sweet.