How Worried Should You Be? Petrol in a Diesel Car in Ascott-under-Wychwood
Probably less than you already are — as long as no one has started the vehicle. Everyone in Ascott-under-Wychwood begins with "have I wrecked it?", and the fair answer is generally no: petrol left inside your tank of a diesel stays harmless until priming, cranking or driving pulls it into the system. To keep it that way, call Petrol in Diesel then leave the motor alone. Further down, this page sets out what petrol really does inside a diesel, how far it may have gone, and how to stop it happening to you again.
What petrol in a diesel does to your engine
On its way through a motor, diesel does two tasks. It protects to begin with, and only then does it burn. Made to very fine gaps, the fuel injectors and the pump rely on your diesel moving through them to keep their surfaces from wearing against one another.
The second job petrol doesn't do at all, and the first it does badly. The knocking comes from petrol being made not to ignite when compressed, which is exactly the opposite of what a diesel needs. On top of that it is runnier than diesel, it strips away the protection the fuel system hinges on, and any pump running on such a mixture is wearing itself.
Seen together, they show what shape the trouble has. It's circulation that causes the harm, not contact. All a tank with petrol in it amounts to is a fuel issue. Whatever a worn pump sheds goes on, carried by your fuel, into the fuel injectors further along, which is why a pump that has worked on the petrol is where a mechanical fault starts.
How bad is petrol in a diesel? Four situations we see around Ascott-under-Wychwood
Fuelled but never started — as good as it gets. Being on a forecourt is what makes this possible: elsewhere, the car has been driven there to begin with. With the petrol held inside that tank alone, it is drained and flushed right where it stands, and nothing more is needed.
Ignition on, or started for a moment. The fuel system has been bled, and so petrol has left your tank and got to the fuel filter and your lines. Still usually straightforward: drain, flush, and the filter seen to.
The pump now worked a few miles on thinned fuel — that's what driving it does. Mileage is only half of it; how hard it was driven counts just as much. Either way this work includes your tank, the lines, the fuel filter and clean fuel through the whole circuit. Driving the children to Wychwood Church of England Primary School is one kind of trip. Driving as far as Oxford, under 25 miles away, makes a very different job — as does any mileage on the M40, under 25 miles from Ascott-under-Wychwood, with the motor running hard all the way.
Knocking, a ragged idle, smoke, a throttle gone soft: driven till it complained. The motor is telling you the fuel is no longer behaving like diesel. Leave it where it stops: a lay-by, a quiet street, the verge on Heritage Lane. A vehicle stopped soon very rarely has long-term damage, since the drain and the flush-through, which still come first, take care of it.
What Ascott-under-Wychwood people get told about petrol in a diesel — and the stories in it
It will not be fine. The myth: "Fill it the rest of the way with diesel and it'll be." Topping up takes out nothing; it gives you a fuller tank of the same mix. A diesel fuel system does not tolerate petrol by percentage in the way that advice presumes.
"Modern diesels can handle a little petrol" — a myth, and closer to the reverse. Protection counts more on newer diesels, not less, since their fuel passes through more precise components at higher pressure.
Myth: "If it starts and drives, there's no damage done." This is the one that fools people. A petrol motor fed diesel generally won't run, so the motorist stops and the harm stops with them. A diesel fed petrol usually starts, ticks over and drives away as if nothing has happened, whilst the pump wears. Being able to run is not proof of being fine.
Not so: a two-stroke additive lets you to drive home. It is an old fix, supposed for another problem. It doesn't put back what petrol has diluted, and that petrol is still inside that tank afterwards.
"Drain it yourself and you're sorted" — a myth, since after it's been running some petrol lies in the filter and lines, waiting to go right back through the pump on the next start. And, a can of petrol filled at the roadside is genuinely dangerous.
How does petrol in a diesel happen?
It's rarely carelessness, and no one does it on purpose. A diesel nozzle generally will not fit a petrol vehicle, yet the smaller petrol nozzle goes into the filler of a diesel almost without resistance — so forecourts make this one error easy, and only in one direction.
Routine and your car falling out of step is how it takes place. Courtesy car, hire car, or a vehicle that's new. One petrol and one diesel on the driveway of the same household. Your normal forecourt, its pumps now in a different order. Filling up in a hurry en route to the nearest station, with a train to catch. Years of petrol cars behind you, a diesel Renault Megane in front of you on the forecourt for its first tank — that's when. The hand repeats what it has always done once you add rain, a phone call or a back seat full of children.
Avoiding petrol in a diesel next time you fill up around Ascott-under-Wychwood
- 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.
- In a motor you do not know, look inside the flap over your filler or at the cap before your first fill: many vehicles print the fuel type there.
- Mark your key. In a home with one of each, a coloured fob or a sticker on the diesel's key does more than any amount of meaning to remember.
- Before the nozzle comes off the petrol pump the first time you fuel a hired or new vehicle, say "diesel" out loud. Daft, yes, but it does the trick.
- Whilst you're thinking about something else, this is an easy mistake to make — so put the 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 are available for vehicles without one. They are a backstop, not a reason to stop checking the pump.
- Stop the moment you realise. Less petrol in your tank makes a thinner mixture. It does not change what to do next, which is still not to start the vehicle.
Already put petrol in a diesel in Ascott-under-Wychwood?
Then, there is just a short order of things. Starting it is out, and so is switching on your ignition. Ask the staff to help you roll it away from the pump if you're still at the forecourt, whether that's Gulf or somewhere else. Ring 0333 366 0103 next, with three answers — the fuel, the rough quantity, and whether it's run.
AdBlue, not petrol? Then say so. Corrosion and deposits, not lost protection, make it a separate fault — Ascott-under-Wychwood has a page all for it.
One petrol in a diesel task in Ascott-under-Wychwood costs more than another. Why?
There is no fair single price for this, since the four scenarios above are four separate tasks. Mostly, your cost shifts with which one you are in. Two things come after that: the petrol that went in as a proportion of what your tank takes, then the spot the vehicle is in and whether a technician can reach it safely.
Three queries come first, before quoting, rather than after — what went in, how much, has it run — and that is the reason. Their replies are what turn a range into one firm number.
About Ascott-under-Wychwood
Ascott-under-Wychwood is a small village in Oxfordshire, situated on the banks of a river at an elevation of around 100 metres. Ascott-under-Wychwood lies near the villages of Ascott d'Oyley and Ascott Earl, and is approximately 15 miles from Oxford. Ascott-under-Wychwood has a population of around 550 people, predominantly living in semi-detached houses. Ascott-under-Wychwood is also within commuting distance of London, being about 66 miles away.
Fuel drain cover across Oxfordshire, Ascott-under-Wychwood included
Petrol in diesel jobs in Ascott-under-Wychwood — part of the OX postcode area — go to vans that likewise cover the spots round it, Ascott d Oyley, Ascott Earl and Chilson among them. You need not bring your vehicle to us. Forecourts, supermarket car parks, lay-bys and your own drive are all locations we drain.
Still at the pump around Ascott-under-Wychwood?
The best place there is, then — that's where you are. Keep the vehicle turned off, then ring.