Petrol in a Diesel Car in Greasby: How Worried Should You Be?
Provided it has not been started, you can worry less than you probably are. Everyone in Greasby begins with "have I wrecked it?", and the fair answer is normally no: petrol left inside the tank of a diesel remains harmless until priming, cranking or driving pulls it into the fuel system. Leave your motor off and ring Petrol in Diesel — that is how you keep it that way. The rest of this page covers what petrol actually does to a diesel, how to judge how far it has got, and how to make sure it does not happen to you a second time.
What petrol in a diesel does to the engine
Two jobs fall to diesel on its route through a motor. Before it ignites, it protects — and then it combusts. Designed to very fine tolerances, your injectors and your pump rely on your diesel flowing through them to keep their surfaces from wearing against one another.
The second task petrol does not do at all, and the first it does poorly. The knocking comes from petrol being designed not to ignite when compressed, which is precisely the reverse of what a diesel needs. On top of that it is runnier than diesel, it strips away the lubrication the fuel system hinges on, and any pump working on such a mix is wearing itself.
Taken together, they show the shape the problem has. Contact doesn't do the damage — movement does. Petrol in the tank is a fuel fault. Whatever a worn pump sheds goes on, carried by the fuel, into your injectors downstream, which is why a pump that has been working on the petrol is where a mechanical fault starts.
Four situations we see in Greasby: how serious is petrol in a diesel?
Filled up, never started. The best case there is. That petrol is in your tank and only your tank, and the task is a drain and a flush where your car sits. This is the one scenario that can only truly occur at a forecourt, because anywhere else the car has been driven to get there.
Ignition on, or started for a second. Petrol has come out of the tank and got to the fuel filter and the fuel lines, since the system has been primed. Usually nothing more than clearing, purging and sorting your filter, and so still easy.
Driven a couple of miles. Now your pump has spent these miles working on diluted fuel. Tank, lines, filter, then fresh fuel put through the entire circuit: that's this work, and the way your car was driven matters as much as the miles. A school run to Greasby Infant School is one matter. A run as far as Liverpool, under 10 miles away, is a very different job. So is any mileage on the Moreton Spur, under 3 miles from Greasby, where the motor has been labouring hard the whole time.
Driven until it protested. Rattling, a ragged idle, smoke, a throttle that has gone soft. The fuel is not behaving like diesel any more, and the motor is saying so. Whether it's the verge on MacDonald Drive, a lay-by or a side street, stop where you are and leave it. A vehicle pulled over early very rarely has lasting damage, since the fuel drain and the flush-through, which still come first, deal with it.
What Greasby motorists get told about petrol in a diesel — and the myths in it
Myth: "Fill it the rest of the way with diesel and it'll be fine." It will not. Nothing is removed by topping up — you're left with a fuller tank, still the same mixture. That advice supposes a diesel fuel system tolerates petrol by percentage. It doesn't.
Not so: a modern diesel copes with a bit of petrol. Rather, the reverse. At higher pressure, through smaller components: that's how a modern diesel moves its fuel, so the protection counts more, not less.
Myth: "If it starts and drives, there's no damage done." This is the one that catches drivers. Feed diesel to a petrol motor and it normally won't run, so the motorist stops — and the harm stops with them. Feed petrol to a diesel and it generally starts, idles and pulls away like nothing happened — all the while its pump is wearing. Fine and running aren't the same thing.
Myth: a two-stroke additive lets you to drive home. It is an old fix, supposed for another problem. What petrol has weakened stays weakened, and that petrol stays in the tank regardless.
Once the engine has run, part of the petrol sits in the fuel filter and the fuel lines, not your tank — and the next start sends it straight back through the pump. So the myth "drain that tank yourself and you're sorted" doesn't stand up. It is also really dangerous to drain petrol into a can at the roadside.
How does petrol in a diesel occur?
Carelessness is rarely the cause, and nobody means to do it. One way only, because of the nozzles: the slimmer petrol one slides inside a diesel filler with almost no resistance, while the diesel one generally won't fit a petrol car. That is how the forecourt makes it simple.
The moment habit stops matching your car is the moment it happens. Courtesy car, hire car, or a car that is brand new. Households running one of each, petrol and diesel. Your usual forecourt, its pumps now in a different order. Rushing for a train outside Upton and fuelling up en route. Years of petrol vehicles behind you, a diesel Volkswagen Golf in front of you on the forecourt for its first tank — that is when. Throw in a back seat full of children, a phone call or rain, and the hand takes over.
Greasby drivers: how to prevent petrol in a diesel next time
- The label is what matters, so read the petrol pump rather than the colour: in the UK unleaded handles are normally green and diesel black, but not on each forecourt.
- Many vehicles state the fuel type inside the filler flap or on the cap, so check it on the first fill in a motor you don't know.
- Label the key. In a house with one of each, a coloured fob or a sticker on the diesel's key does more than any amount of intending to remember.
- Before the nozzle comes off the petrol pump the first time you fuel a hired or new motor, say "diesel" out loud. Daft, perhaps, but it works.
- Mistakes like this are straightforward to make whilst your mind is on something else, and so the phone goes away.
- A misfuel inhibitor helps, up to a point. Some diesels have a filler designed to refuse a petrol nozzle, and add-on devices are available for motors without one. They are a backstop, not a reason to stop checking the pump.
- Stop as soon as you notice. Less petrol inside your tank means a thinner mix. It does not change what to do next, which is still not to crank it.
Put petrol in a diesel in Greasby already?
Then the order of things is short. Don't turn the ignition on, and don't start it. Ask the attendants to help you roll it clear of the pump if you're still on the forecourt, whether that is BP or anywhere else. Then call 0333 366 0103 and tell us what was put in, roughly how much, and if it's run.
Say so if it was AdBlue instead of petrol: it's a separate problem, with its own page for Greasby, since AdBlue brings corrosion and deposits instead of lost lubrication.
Why one petrol in a diesel job around Greasby costs more than another
There's no honest single price for this, because the four scenarios above are four different tasks. What moves the cost is chiefly which of them you're in. After that it's the share — how much petrol was put in against how much that tank takes — and after that where the vehicle is and whether a technician can reach it safely.
Three queries come first, before quoting, instead of after — what was put in, how much, has it run — and this is the reason. Given the replies, you get a straight figure rather than a range.
About Greasby and its setting
Greasby is a coastal village in Merseyside, situated approximately 6 miles from Liverpool and 180 miles from London. Greasby has a population of around 3418 people and is characterised by semi-detached housing. Greasby sits at an elevation of 28 metres, with nearby places including Upton Meadow, Frankby, and Irby Hill. Greasby is part of the wider North West region of England, with the Irish Sea to the west.
Fuel drain cover across Merseyside, Greasby included
Our teams answering petrol in diesel calls in Greasby, in the CH postcode area, also work the locations around it, Upton Meadow, Frankby and Irby Hill included. Our engineers drain where your vehicle is — your own drive, a lay-by, a supermarket car park, a forecourt — so it never needs to come to us.
Still at the petrol pump in Greasby?
The best position there is, then — that is where you are. Phone, and keep it switched off.