Should You Worry? Petrol in a Diesel Car in Wawne
Far less than you likely are, provided it has not been started. Till your ignition primes the pump, your starter cranks, or your vehicle is driven, petrol in a diesel tank just sits there and does no harm. Which means the honest reply to that first Wawne query — "have I ruined it?" — usually no. Leave the engine off and ring Petrol in Diesel — that keeps it that way. Further down, you will find what petrol actually does inside a diesel, how far it may have gone, and how to stop it happening to you a second time.
Petrol in a diesel: what does it do to the engine?
On its way through an engine, diesel does two tasks. It burns, and before it burns it lubricates. Designed to very fine tolerances, the injectors and your pump depend on your diesel moving through them to keep their surfaces from wearing against one another.
Petrol does the first job badly and the second not at all. The knocking comes from petrol being designed not to ignite when compressed, which is exactly the reverse of what a diesel needs. On top of that it is runnier than diesel, it strips away the lubrication the fuel system rests on, and any pump running on that mix is wearing itself.
Put those together and the shape of the problem is clear. Contact doesn't do the damage — circulation does. Where that petrol is only in your tank, it is a fault of fuel, nothing more. The start of a mechanical problem is a pump that has been working on that petrol — and whatever a worn pump sheds moves on with the fuel to the injectors beyond it.
How serious is petrol in a diesel? Four situations our engineers see around Wawne
The best case there is: filled up, not once started. Being on a forecourt is what makes this possible: elsewhere, the vehicle has been driven there to begin with. With the petrol kept inside the tank alone, it is drained and flushed right where it stands, and nothing more is needed.
Started for a second, or just your ignition on. Petrol has left your tank and reached the filter and the lines, since your system has been bled. Still normally easy: drain, flush, and the fuel filter dealt with.
A couple of miles driven, and your pump has spent every one of them labouring on weakened fuel. How hard the vehicle was driven matters as much as how far, and the work takes in that tank, the fuel lines, the fuel filter and fresh fuel through the whole circuit. A school run to Wawne Primary School is one thing. Very different again: a trip to Kingston upon Hull, under 10 miles away, or any miles on the M62, under 15 miles from Wawne, where your engine kept labouring hard.
It protested, and only then stopped: smoke, knocking, a throttle gone soft, an idle gone uneven. The fuel is not acting like diesel any more, and the motor is saying so. Leave it wherever it has stopped: a lay-by, a quiet street, the verge on Sutton Road. The drain and flush-through still go first, and they take care of it: if a car is pulled over quickly, long-term damage is very uncommon.
Wawne motorists and the petrol in a diesel stories they hear
Myth: "Fill it the rest of the way with diesel and it will be fine." It will not. A bigger tank of the same mixture is all it gives, because topping up removes nothing. That advice supposes a diesel fuel system tolerates petrol by percentage. It doesn't.
"Newer diesels can handle a little petrol" — a myth, and closer to the reverse. Lubrication counts more on current diesels, not less, because their fuel runs through smaller parts at higher pressure.
Myth: "If it starts and drives, there is no harm done." This is the one that catches motorists. The motorist of a petrol motor fed diesel usually stops, since it will not run, and the damage stops with them. Feed petrol to a diesel and it usually starts, idles and pulls away as if nothing happened — all 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 problem. It does not put back what petrol has weakened, and that petrol is still inside that tank later.
Once the engine has run, part of that petrol is in the filter and the fuel lines, not that tank — and the next start pulls it straight back through the pump. So the myth "drain that tank yourself and you're sorted" does not stand up. Besides, petrol emptied into a can by the road is genuinely dangerous.
How does petrol in a diesel take place?
It's seldom carelessness, and no one does it on purpose. A diesel nozzle mostly won't go into a petrol car, but the smaller petrol nozzle goes into the filler of a diesel nearly without resistance — so forecourts make this one mistake easy, and only in one direction.
It occurs when routine and your car stop matching. Hire cars, courtesy cars, and motors that are new to you. A household with one petrol and one diesel on the drive. The pumps in a different order on a well-known forecourt. A hurried fill en route to Cottingham with a train to catch. Years of petrol motors behind you, a diesel Renault Clio in front of you on the forecourt for its first tank — that is when. Add a back seat full of kids, a phone call or rain, and the hand takes over.
Wawne motorists: how to prevent petrol in a diesel next time
- Read the pump, not the colour. In the UK unleaded handles are usually green and diesel black, but not on every forecourt. The label is what matters.
- The first fill in an unfamiliar vehicle is the time to check your filler flap — inside it, or on the cap, many motors state the fuel they take.
- Good intentions count for less than a sticker or a fob in a vivid colour on your diesel's key when a household has one of each. So mark it.
- Say it before you lift it. On your first fill in a new or hired car, say "diesel" out loud before you take the nozzle off the petrol pump. It seems silly and it does the trick.
- While you are thinking about something else, this is an easy mistake to make — so tuck the phone away.
- Add-on devices are available for cars without one, and some diesels are built with a filler that will not take a petrol nozzle. Useful — but a safety net only, never a reason to stop checking the label.
- The moment you realise, stop: less petrol in your tank means a thinner mix. What to do next doesn't change, though — still don't crank it.
Put petrol in a diesel around Wawne already?
The order of things is short, then. Starting it is out, and so is switching on the ignition. Ask the staff to help you roll it away from the pump if you are still at the forecourt, whether that is Asda or somewhere else. Next, 0333 366 0103. We will ask what went in, about how much, and if it's been run.
If it was AdBlue and not petrol, say so. That is a different issue — corrosion and deposits and not lost lubrication — and it has its own page for Wawne.
One petrol in a diesel task in Wawne costs more than another. Why?
The four scenarios above are four separate jobs, so no single price for this would be fair. What shifts your cost is mostly which of them you're in. Beyond that it's the ratio — how much petrol got in against how much that tank holds — and after that where the vehicle is and whether a van can get to it safely.
That is why we ask three queries before costing rather than after: what got in, how much, and if it has run. Given the replies, there is a straight figure rather than a range.
About Wawne, briefly
Wawne is a small village in the East Riding of Yorkshire, situated near the city of Kingston upon Hull. Wawne lies in a low-lying area, with an elevation of around 6 metres, and is surrounded by other nearby places such as Midmeredales and Thearne. Wawne has a population of approximately 1021 residents, who mostly live in semi-detached housing. Wawne is located about 5 miles from Kingston upon Hull, making it a commuter-friendly village.
Across East Riding of Yorkshire and around Wawne: fuel drain cover
Wawne waits in the HU postcode area, and the teams that answer petrol in diesel calls there work the locations near it as well — Midmeredales, Thearne and Meaux among them. A forecourt, a supermarket car park, a lay-by or your own drive are all locations our engineers work, and the vehicle doesn't need to come to us.
Wawne: still at the pump?
In that case, you couldn't be in a better position. Keep it off. Phone.