Petrol in a Diesel Car in Stillington: How Worried Should You Be?
Less than you probably are, provided it hasn't been started. "Have I wrecked it?" is the first thing everyone around Stillington asks, and the honest answer is generally no, because petrol left in a diesel tank hurts nothing till it is dragged through your fuel system — by ignition priming, by the starter, or by being driven. To keep the vehicle that way, call Petrol in Diesel and leave the engine switched off. The remainder of this page explains what petrol actually does to a diesel, how to judge how far it has got, and how to make sure it doesn't happen to you a second time.
Petrol in a diesel: what does it do to your engine?
Passing through a motor, diesel does two things at the same time. It ignites, and before it ignites it lubricates. Very fine tolerances are built into the fuel injectors and your high-pressure pump, and just the diesel running through stops their surfaces grinding together.
Petrol handles the first task poorly and the second not at all. Being less viscous than diesel, petrol strips away the protection a fuel system needs, leaving a pump on the blend wearing itself. It's equally made to resist igniting under compression — the reverse of what a diesel needs — which is where you get the knocking.
Combined, those make the shape of the problem clear. It's circulation that causes the damage, not contact. Any tank with petrol in it is a fuel issue. The start of a mechanical problem is a pump that has been labouring on that petrol — and whatever a worn pump sheds travels on with your fuel to your injectors downstream.
Petrol in a diesel in Stillington: how serious is it? Four cases
Fuelled up, never started. The best case there is. Being on a forecourt is what makes this possible: elsewhere, the car has been driven there to begin with. With that petrol kept inside the tank alone, it is cleared and purged on the spot, and nothing more is needed.
Started for a second, or only the ignition on. With the fuel system primed, your lines and filter now hold petrol that has come from that tank. That is generally still an easy task — a drain, a flush, and the filter dealt with.
A couple of miles driven, and the pump has spent each of them working on weakened fuel. The work is that tank, your lines, your filter and clean fuel through the entire system, and how hard the vehicle was driven matters as much as how far. A school run to Stillington Primary School is one matter. Driving as far as York, under 10 miles away, makes a very different job — as does any distance on the A1(M), under 15 miles from Stillington, with your engine working hard the whole time.
Driven on till it complained — rattling, smoke, a lumpy idle, a soft throttle. That's your motor telling you its fuel has stopped behaving like diesel. Leave it where it has stopped: a lay-by, a quiet street, the verge on Main Street. A car stopped soon very rarely has permanent damage, as the drain and the flush-through, which still come first, take care of it.
What Stillington drivers get told about petrol in a diesel — and the myths in it
"Top it up the rest of the way with diesel and it'll be fine" — a myth. It will not. Topping up takes out nothing; it gives you a bigger tank of the same mixture. The assumption behind the advice — that diesel fuel systems accept petrol by percentage — is wrong.
"Newer diesels can handle a little petrol" — a myth, and nearer the opposite. A newer diesel sends its fuel through finer components at higher pressure, which makes the lubrication matter more, not less.
This is the one that catches motorists. Myth: "If it starts and drives, there is no harm done." Any petrol motor fed diesel normally won't run, so the motorist stops and the harm stops with them. Nothing seems to have happened when a diesel fed petrol fires up, ticks over and drives away, which it usually does; meanwhile your pump wears. Fine and running are not the same thing.
Not so: a two-stroke additive makes it safe to drive home. It is an old workaround, meant for another issue. What petrol has diluted remains thinned, and the petrol stays in that tank regardless.
Myth: "Drain the tank yourself and you're sorted." After the engine has been run, some of that petrol is no longer inside the tank: it is in your filter and the fuel lines, and it goes straight back through your pump on the next start. Also, a can of petrol filled by the kerbside is genuinely risky.
How petrol ends up: petrol in a diesel
Carelessness is seldom the cause, and no one means to do it. The forecourt makes it easy: the petrol nozzle is the slimmer of the two, and it slips into a diesel filler with almost no resistance, whilst a diesel nozzle generally will not go into a petrol car at all. So the mistake runs one way.
Habit and your car falling out of step is how it happens. A new vehicle, a hire car or a courtesy car. Two motors on one driveway, one petrol, one diesel. Your normal forecourt, its pumps suddenly in a different order. A hurried fill en route to Poppleton with a train to catch. Precisely the moment it occurs: after years of driving petrol, a driver fills a diesel Renault Megane for the first time. Throw in rain, a phone call or a back seat full of kids, and your hand repeats what it has always done.
Next time you fill up around Stillington: preventing petrol in a diesel
- Read the petrol pump, not the colour. In the UK unleaded handles are generally green and diesel black, but not on each forecourt. The label is what matters.
- Check your filler flap. Many cars state the fuel type inside the flap or on the cap. Look at it on the first fill in a vehicle you don't know.
- One of each in the household? Mark your key to the diesel — a bright fob, a sticker — because meaning to remember is not enough.
- "Diesel", out loud, before you pick up the nozzle — every time a new or hired car gets its first tank. It seems silly. It works.
- Thinking about something else is when this becomes an easy mistake to make, and so tuck the phone away then keep your mind on the pump.
- Up to a point, a misfuel inhibitor helps: some diesels have a filler built to reject a petrol nozzle, and aftermarket devices exist for the rest. Count it as a safety net, and keep reading the pump.
- Less petrol means a weaker mixture, and so stop as soon as you notice — while remembering that the next step is unchanged. It's still not to start the car.
Put petrol in a diesel in Stillington already?
In that case, there is just a short order of things. Starting it is out, and so is switching on your ignition. If you are still on the forecourt — the nearest petrol station or anywhere else — ask the staff to help you roll the car away from the petrol pump. Then call 0333 366 0103 and tell us what got in, roughly how much, and if it has run.
If it was AdBlue instead of petrol, say so. That's a different fault — corrosion and deposits instead of lost protection — and it has its own page for Stillington.
One petrol in a diesel task in Stillington costs more than another. Why?
There is no honest single price for this, since the four scenarios above are four different tasks. Mostly, the cost shifts with which one you're in. The ratio counts next, meaning how much of the tank is petrol, followed by the position of your car and whether getting to it is safe for a van.
Ahead of any quote, not after, we ask three queries: your fuel that went in, its volume, and whether it has run. That's why. Those answers change a range into a straight figure.
About Stillington itself
Stillington is a small village in North Yorkshire, situated approximately 9.8 miles north of York, and is characterized by its detached housing stock. Stillington sits in a relatively low-lying area, with an elevation of around 47 metres, and is surrounded by nearby places such as Marton-in-the-Forest and Huby. Stillington remains a quiet, rural community with a population of around 573 residents. Stillington is also located near the village of Moxby, and is about 184 miles from London.
Fuel drain cover around Stillington and across North Yorkshire
The vans answering petrol in diesel calls in Stillington, in the YO postcode area, also work the locations around it, Marton-in-the-Forest, Moxby and Huby included. The vehicle doesn't 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 Stillington?
Then you are in the best place there is. Switched off it remains; then call.