Goose Green: Petrol in a Diesel Car? How Worried to Be
Likely less than you already are — as long as no one has started it. Till the ignition primes your pump, your starter turns, or your vehicle is driven, petrol in a diesel tank just waits there and does no harm. Which makes the truthful reply to the first Goose Green query — "have I ruined it?" — normally no. Petrol in Diesel is who to ring, with your engine kept off, so it remains that way. Read on for three things: the effect petrol has inside a diesel engine, the signs of how far it has spread, and ways to make sure you never repeat it.
Inside your engine: what petrol in a diesel really does
On its way through a motor, diesel does two tasks. Before it combusts, it protects — then it burns. Your high-pressure pump and the fuel injectors are designed to extremely fine gaps, and the diesel passing through them is what stops those surfaces from grinding against each other.
The second job petrol doesn't do at all, and the first it does poorly. The knocking comes from petrol being designed not to ignite when compressed, which is exactly the opposite of what a diesel needs. On top of that it is thinner than diesel, it strips away the lubrication your system depends on, and any pump running on that mixture is wearing itself.
Put those together and the shape of the trouble is plain. It's circulation that does the harm, not contact. Where the petrol is only inside your tank, it's a problem of fuel, nothing more. The beginning of a mechanical problem is a pump that has been labouring on that petrol — and whatever a worn pump sheds moves on with your fuel to the fuel injectors beyond it.
How serious is petrol in a diesel? Four situations our technicians see around Goose Green
Fuelled but never started — as good as it gets. Being on a forecourt is what makes this possible: elsewhere, your car has been driven there to begin with. With the petrol held inside your tank alone, it's drained and cleaned right where it stands, and nothing more is needed.
A brief spell of running, or just the ignition on. Once primed, your system has drawn petrol out of your tank as far as the fuel filter and your lines. Drain, flush, see to the filter: still normally straightforward.
A couple of miles driven, and the pump has spent every one of them labouring on diluted fuel. Tank, lines, filter, then clean fuel put through the whole system: that is this work, and the way the vehicle was driven counts as much as the distance. On the school run to the local primary school, the miles is small. Very different once more: a run to Edinburgh, under 10 miles away, or any distance on the M8, under 15 miles from Goose Green, where the engine kept working hard.
It protested, and only then stopped: smoke, knocking, a throttle gone soft, an idle gone uneven. The motor is telling you the fuel is no longer acting like diesel. Whether it's the verge on Goose Green Avenue, a lay-by or a side road, stop where you are then leave it. The fuel drain and flush still go first, and they take care of it: if a car is stopped quickly, long-term damage is very uncommon.
What Goose Green drivers get told about petrol in a diesel — and the myths in it
It will not be fine. The myth: "Fill it the rest of the way with diesel and it will be." Nothing is removed when you top up — the tank simply carries more of the same mixture. A diesel fuel system does not accept petrol by percentage in the way that guidance supposes.
Myth: "A newer diesel can cope with a bit of petrol." If anything, the reverse. Finer components and higher pressure are the way a modern diesel runs its fuel, and that makes the protection matter more, not less.
Myth: "If it starts and drives, there's no harm done." This is the one that catches drivers. Any petrol engine fed diesel generally will not run, and so the driver stops and the damage stops with them. Feed petrol to a diesel and it usually starts, ticks over and drives away as if nothing happened — all the while its pump is wearing. A running engine does not mean fine.
Myth: "Add some two-stroke oil and drive the vehicle home." It is an outdated fix for a distinct fault. It doesn't put back what petrol has thinned, and that petrol is still in that tank after that.
"Drain it yourself and you're sorted" — a myth, since after it has been running some petrol sits in the fuel filter and lines, ready to go right back through the pump on the next start. On top of that, petrol cleared into a can by the road is truly hazardous.
How does petrol in a diesel take place?
It is seldom carelessness, and nobody does it on purpose. The petrol nozzle is the slimmer of the two and slips into a diesel filler with almost no resistance; a diesel nozzle generally won't go into a petrol motor at all. The forecourt makes it easy, and the slip runs one way.
The moment routine stops matching the car is the moment it occurs. A new car, a hire car or a courtesy car. Households running one of each, petrol and diesel. A forecourt you know, but with its pumps laid out differently. Rushing for a train at Musselburgh and filling up en route. A new-to-you diesel Volkswagen Golf, its first fuelling, and a driver used to petrol: exactly when it happens. Add rain, a phone call or a back seat full of kids, and the hand repeats what it has always done.
Next time you fill up in Goose Green: preventing petrol in a diesel
- The label is what counts, so read the pump instead of the colour: in the UK unleaded handles are normally green and diesel black, yet not on every forecourt.
- In a car you don't know, look inside the flap over your filler or at the cap before the first fill: plenty of cars state the fuel there.
- Good intentions do less than a sticker or a fob in a vivid colour on your diesel's key if a house has one of each. So label it.
- "Diesel", out loud, before you lift the nozzle — each time a new or hired car needs its first tank. It seems silly. It does the trick.
- Tuck the phone away. This is an easy mistake to make while you are thinking about something else.
- Add-on devices are available for motors without one, and some diesels are built with a filler that will not take a petrol nozzle. Helpful — but a backstop at best, never a reason to stop checking the label.
- Less petrol makes a weaker mix, so stop the moment you realise — though remembering that the next stage is unchanged. It's still not to start the car.
Petrol already in a diesel around Goose Green? Begin here
Short and simple, then, is the order of things. Don't turn the ignition on, and don't fire it up. The staff at the forecourt — whether at Tesco itself or wherever you filled up — will usually help roll it away from the pump if you ask. Then phone 0333 366 0103 and tell us what got in, about how much, and if it has run.
Say so if it was AdBlue rather than petrol: it is a separate fault, with its own page for Goose Green, because AdBlue brings corrosion and deposits rather than lost lubrication.
Goose Green petrol in a diesel tasks: why one costs more than another
Four different tasks sit behind the four situations above — which is why there is no fair single quote. Chiefly, your cost moves with which situation you're in. Two things follow that: the petrol that was put in as a proportion of what the tank takes, then the place your car is in and whether our van can reach it safely.
What was put in, how much, and if it has run — three questions our technicians ask before costing, not after, for precisely that reason. A range becomes a straight figure when those replies are in.
About Goose Green and where it is
Goose Green is a coastal suburban area in East Lothian, situated near the city of Edinburgh and close to the towns of Musselburgh and Fisherrow. Goose Green lies at a low elevation of around 5 metres, reflecting its proximity to the sea. Goose Green has a mix of residential properties, with flats being the predominant type of housing in the area. Goose Green is located approximately 5 miles from Edinburgh, making it a commuter-friendly location.
Fuel drain cover in Goose Green and across East Lothian
Petrol in diesel calls around Goose Green — part of the EH postcode area — go to vans that also cover the locations around it, Musselburgh, Lewisvale and Fisherrow among them. The vehicle does not need to move to us: we drain at a forecourt, in a supermarket car park, in a lay-by or on your own drive.
Goose Green: still at the petrol pump?
Nothing beats it: that's where you are. Keep it off. Ring.