Help! Petrol in a diesel engine (Passat TDi)

Red Kev

Sitting here looking at a neighbours car. 03 Passat diesel TDi (red i). Seems he put about 3 litres of petrol into it by accident chatting to somebody at the station and needs to know what to do.

Tank is over half full, so about 35l of diesel in it already along with the 3l of petrol.

He has just driven 8km home, no mishaps, no misfiring etc.

He needs to leave home at 6.30 am tomorrow and will do a round trip of 350km on motorway and fast N-roads, he needs the car for work and finding a replacement in the meantime is going to be very difficult.

Very isolated area, not much chance of a rescue service getting here and he needs a car tomorrow.

So does he:

1) Leave it, it's fine and the 10% dilution will do no long term harm to the engine.

2) Drive back to the petrol station and fill it up so it's 3:60 or 5% dilution and this will do no harm.

3) Get it siphoned off immediately as it's going to cost more in the long term to fix it, or it might even run into some bloody limp mode at some stage tomorrow.


Can't help him myself with advice as I usually drive much older Mercs and Toyota Hiace vans and 10% petrol would be no bother to them, not so sure about newer engines and electronics.

Thanks. All advice welcome.

....and yes, he knows he's a tit for having this happen but it can happen to the best of us at times.

Cleveland Hot Pocket

Is that the same engine as in the Mark4 golf?

If so, fill her to the brim and it will be grand. 3 liters in a full tank will be no harm. Might even find an increase in mpg for the next while.

Cleveland Hot Pocket

link to my previous post about this,actually.
http://www.boards.ie/vbulletin/showpost.php?p=86741386&postcount=4

Dermo123

No bother with that. Might think this is ridiculus but it might be no harm to shake the car a bit in the morning before he starts it. Petrol and diesel may separate while siting overnight and a high concentration of petrol might end up on top of diesel. I put a 25% concentration of petrol in an audi 1.9TDI a few years ago and did not purge anything and it is still going fine and passing NCT's etc

Green Hornet

Dermo123 wrote: »

No bother with that. Might think this is ridiculus but it might be no harm to shake the car a bit in the morning before he starts it. Petrol and diesel may separate while siting overnight and a high concentration of petrol might end up on top of diesel. I put a 25% concentration of petrol in an audi 1.9TDI a few years ago and did not purge anything and it is still going fine and passing NCT's etc

Not true about the separating - petrol and diesel are miscible, they won't separate without refining.

George Dalton

As already posted, it will be absolutely fine.

Red Kev

Cheers for all that, he filled it up to the brim an hour ago to dilute it as much as possible.