How Worried Should You Be? Petrol in a Diesel Car in Two Mile Ash
Unstarted? Then less anxious than you likely feel. Everyone in Two Mile Ash begins with "have I wrecked it?", and the fair answer is usually no: petrol left in the tank of a diesel stays harmless until priming, cranking or driving draws it into the fuel system. Petrol in Diesel is who to ring, with the engine left off, and so it stays that way. Keep reading for three things: the effect petrol has inside a diesel motor, the clues of how far it has got, 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. It protects first, and only then does it burn. Very fine gaps go into your injectors and the high-pressure pump, and only your diesel flowing through keeps their surfaces from grinding together.
Poorly at the first, not at all at the second: that is petrol. A pump working on a petrol mix is wearing itself out, because petrol is runnier than diesel and takes away the lubrication your fuel system relies on. Petrol is also designed to resist igniting under compression — the opposite of what a diesel needs from its fuel — and that's where the knocking starts.
The shape of the trouble is clear when you put those together. The damage is done by movement, not by contact. Petrol in a tank is a fuel problem. Whatever a worn pump sheds travels on, borne by the fuel, into the injectors downstream, which is why a pump that has been working on the petrol is where a mechanical issue starts.
How bad is petrol in a diesel? Four situations our engineers see around Two Mile Ash
The best case there is: filled up, never started. Being at a forecourt is what makes this the case: elsewhere, your car has been driven there to begin with. With the petrol held in your tank alone, it is emptied and cleaned right where it stands, and nothing more is needed.
A brief spell of running, or just your ignition on. With the fuel system primed, the fuel lines and filter already hold petrol that has come from your tank. That's generally still a straightforward task — a drain, a flush, and your filter dealt with.
Those few miles on the road were your pump running on fuel diluted by petrol the whole way. Mileage is only half of it; how hard it was driven counts just as much. Either way this work includes that tank, your lines, your filter and fresh fuel through the whole circuit. On the school run to Two Mile Ash School, the distance is short. A run as far as Milton Keynes, under 3 miles away, is a very different job. So is any distance on the M1, under 5 miles from Two Mile Ash, where your engine has been labouring hard throughout.
It protested, and only then stopped: smoke, clattering, a throttle gone soft, an idle gone uneven. The fuel is not acting like diesel any more, and the engine is telling you. Pull up wherever you are — the verge on V5 Great Monks Street, a lay-by, a side street — and leave the car where it is. Lasting damage is very rare if a vehicle is pulled over quickly, and the fuel drain and flush that still come first sort it out.
Two Mile Ash drivers and that petrol in a diesel myths they hear
"Top it up the rest of the way with diesel and it will be fine" — a myth. It won't. Nothing comes out when you top up — that tank simply holds more of the same blend. That advice assumes a diesel fuel system handles petrol by percentage. It doesn't.
Myth: "A newer diesel can cope with a bit of petrol." If anything, the reverse. A current diesel sends its fuel through smaller components at higher pressure, which makes the lubrication count more, not less.
Myth: "If it starts and drives, there is no damage done." This is the one that fools people. The motorist of a petrol engine fed diesel usually has no choice but to stop, since it will not run, and the harm stops with them. Feed petrol to a diesel and it normally fires up, ticks over and pulls away like nothing has happened — all while its pump wears. Being able to run isn't proof of being fine.
An old fix for a different problem lies behind this one. Myth: "Add some two-stroke oil and drive the car home." What petrol has thinned remains thinned, and the petrol stays in that tank anyway.
Myth: "Drain the tank yourself and you're sorted." Once the engine has been run, some of the petrol is no longer inside your tank: it's in your filter and your lines, and it goes straight back through your pump at your next start. And, a can of petrol drained by the roadside is truly dangerous.
Petrol in a diesel: how does it occur?
On purpose? Never. Through carelessness? Seldom, if ever. A diesel nozzle mostly will not fit a petrol vehicle, yet the narrower petrol nozzle goes into the filler of a diesel nearly without resistance — so forecourts make this one mistake easy, and only in one direction.
When habit and the car stop matching, it takes place. A car that is new to you — a hire car, on loan as a courtesy car, or just bought. One petrol and one diesel on the drive of the same household. The pumps in a different order on a familiar forecourt. Filling up in a rush en route to Wolverton, with a train to catch. A new-to-you diesel Volkswagen Golf, its first fuelling, and a driver used to petrol: exactly when it occurs. 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 around Two Mile Ash: avoiding petrol in a diesel
- Check the pump, not the colour. In the UK unleaded handles are usually green and diesel black, yet not on each forecourt. The label is what counts.
- Many vehicles state the fuel inside the filler flap or on the cap, so check it on your first fill in any vehicle you don't know.
- Good intentions count for less than a sticker or a fob in a vivid colour on the diesel's key if a house has one of each. So label it.
- Before the nozzle comes off the pump the first time you fuel a hired or new car, say "diesel" out loud. Daft, yes, yet it works.
- Whilst you are thinking about something else, this is an easy mistake to make — so put your phone away.
- A misfuel inhibitor helps, up to a point. Some diesels have a filler designed to block a petrol nozzle, and add-on devices exist for motors without one. They are a safety net, not a reason to stop checking the pump.
- Less petrol means a thinner blend, and so stop the moment you notice — while remembering that your next stage is unchanged. It's still not to crank it.
Put petrol in a diesel in Two Mile Ash already?
Short and simple, then, is the order of things. Don't turn your ignition on, and don't crank it. Ask the staff to help you push it clear of the petrol pump if you are still on the forecourt, whether that is BP or anywhere else. What was put in, roughly how much, and whether it has run: tell us that when you call 0333 366 0103.
If it was AdBlue instead of petrol, say so. That's a separate issue — corrosion and deposits rather than lost protection — and it has its own page for Two Mile Ash.
Why one petrol in a diesel job in Two Mile Ash costs more than another
Four separate jobs lie behind the four scenarios above — which is why there is no fair single quote. Which of them you are in is mostly what moves your cost. Where the vehicle is counts too, and whether our van can safely reach it, after the ratio of petrol to what that tank takes.
Ahead of any quote, not after, come three questions: your fuel that got in, the quantity, and whether it has run. That's why. Their answers are what turn a range into one firm number.
About Two Mile Ash, for a moment
Two Mile Ash is a suburban area located on the outskirts of Milton Keynes in Buckinghamshire, situated near the River Great Ouse at an elevation of around 84 metres. Two Mile Ash sits close to nearby places such as Stacey Bushes, Wymbush, and Hodge Lea, and is characterized by its predominantly semi-detached housing stock. Two Mile Ash is a relatively small community, with a population of approximately 3489 residents, and is within commuting distance of London, about 47 miles away.
Fuel drain cover across Buckinghamshire, Two Mile Ash included
Two Mile Ash sits in the MK postcode area, and the teams that answer petrol in diesel calls there work the spots near it as well — Stacey Bushes, Wymbush and Hodge Lea among them. The car does not need to come to us: our technicians drain at a forecourt, in a supermarket car park, in a lay-by or on your own drive.
Still at the petrol pump around Two Mile Ash?
Then, you could not be in a better place. Leave the car turned off, and ring.