How Worried Should You Be? Petrol in a Diesel Car in Upper Rissington
Not started? Then less anxious than you likely feel. Everyone around Upper Rissington begins with "have I wrecked it?", and the fair answer is usually no: petrol left inside the tank of any diesel stays harmless till priming, cranking or driving draws it into the fuel system. Leave your motor off and call Petrol in Diesel — that keeps it like that. The rest 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 does not happen to you a second time.
Petrol in a diesel: what does it do to your engine?
Diesel does two tasks on its way through an engine. It protects to begin with, and only then does it burn. Extremely fine clearances go into the fuel injectors and your high-pressure pump, and just your diesel running through stops their surfaces grinding together.
Of those two jobs, petrol handles the first badly and the second never. The clattering comes from petrol being made not to ignite when compressed, which is exactly the reverse of what a diesel needs. On top of that it is thinner than diesel, it strips out the protection the system rests on, and any pump working on such a blend is wearing itself.
Put these together and the shape of the problem is clear. Not contact but circulation is what causes the harm. Any tank with petrol in it is a fuel problem. After your pump has been labouring on that petrol, a mechanical fault has started: anything shed by a pump that is wearing down is carried downstream to the injectors with the fuel.
Petrol in a diesel in Upper Rissington: how serious is it? Four cases
Filled up, never started. The best case there is. Being on a forecourt is what makes this the case: elsewhere, your car has been driven there to begin with. With the petrol kept inside that tank alone, it's emptied and rinsed on the spot, and nothing more is needed.
A brief spell of running, or merely your ignition on. Petrol has left your tank and got to the fuel filter and your lines, since your system has been bled. That is generally still a straightforward job — a drain, a flush, and the filter dealt with.
Driven a few miles. Now your pump has spent these miles working on weakened fuel. Tank, lines, filter, then clean fuel put through the entire circuit: that is this work, and the way your car was driven counts as much as the mileage. The school run to The Rissington School is one thing. A run as far as Oxford, under 25 miles away, is a very different job. So is any miles on the M5, under 25 miles from Upper Rissington, where the motor has been working hard the whole time.
Driven on until it protested — rattling, smoke, an uneven idle, a dead throttle. The motor is telling you the fuel is no longer behaving like diesel. Whether it is the verge on Snipe Road, a lay-by or a side road, stop there then leave it. Long-term damage is very unusual when a car is stopped early, and the drain and flush that still go first sort it out.
What Upper Rissington drivers 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 will be." Topping up takes out nothing; it gives you a fuller tank of the same mixture. The assumption behind that advice — that diesel fuel systems accept petrol by percentage — is wrong.
If anything, the reverse is true. Myth: "A newer diesel can cope with a bit of petrol." A current diesel sends its fuel through smaller components at higher pressure, which makes the lubrication count more, not less.
This is the one that fools motorists. Myth: "If it starts and drives, there is no harm done." Any petrol engine fed diesel usually won't run, so the motorist stops and the harm stops with them. While your pump grinds, a diesel fed petrol usually starts, idles and drives away as though nothing has happened. Running is not the same as fine.
"A drop of two-stroke oil and drive it home" — a myth, taken from a fix from years ago, for a distinct fault. It doesn't put back what petrol has weakened, and that petrol is still inside your tank afterwards.
The next start draws petrol back round your pump out of your lines and the fuel filter, where some of that ends up after the engine has run. That is why a DIY tank drain does not leave you sorted — a myth. It is also genuinely hazardous to drain petrol into a can at the roadside.
How does petrol in a diesel take place?
Nobody does it on purpose, and it's seldom carelessness. The petrol nozzle is the smaller of the two and slips into a diesel filler with almost no resistance; a diesel nozzle generally won't go into a petrol car at all. The forecourt makes it easy, and the slip runs one way.
It happens when routine and the car stop matching. Courtesy car, hire car, or a vehicle that's brand new. Households running one of each, petrol and diesel. A familiar forecourt with the pumps in a different order. A train to catch, and a rushed fill on the way to Kingham. The first fill-up in a diesel Volkswagen Passat after years of driving petrol is exactly the moment it happens. With rain, a call coming in, or a car full of children to deal with, the hand simply does what it has always done.
Preventing petrol in a diesel next time you fill up around Upper Rissington
- A green handle for unleaded and black for diesel is usual in the UK — but not on each forecourt. Trust the label on the pump, not the colour.
- Check the filler flap. Plenty of vehicles state the fuel inside the flap or on the cap. Look at it on the first fill in a car you do not know.
- One of each in the home? Mark your key to the diesel — a coloured fob, a sticker — since meaning to remember is not enough.
- 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 pump. It seems silly and it does the trick.
- Thinking about something else is when this becomes an easy mistake to make, and so put your phone away and keep your mind on the pump.
- Up to a point, a misfuel inhibitor helps: some diesels have a filler built to block a petrol nozzle, and add-on devices exist for the rest. Treat it as a safety net, and keep reading the pump.
- The moment you notice, stop: less petrol inside that tank makes a weaker mixture. What to do next does not change, though — still don't fire it up.
Already put petrol in a diesel in Upper Rissington?
Short and simple, then, is the order of things. Starting it is out, and so is switching on your ignition. Ask the attendants to help you push it away from the petrol pump if you are still on the forecourt, whether that's The Co-operative Food or somewhere else. Next, 0333 366 0103. We'll ask what went in, roughly how much, and if it's been run.
If it was AdBlue rather than petrol, say so. That is a different issue — corrosion and deposits rather than lost lubrication — and it has its own page for Upper Rissington.
One petrol in a diesel job in Upper Rissington costs more than another. Why?
Four separate jobs lie behind the four situations above — which is why there is no fair single quote. What moves the cost is chiefly which of them you are in. Beyond that it's the share — how much petrol went in against how much your tank takes — and then where the vehicle is and whether our van can reach it safely.
Before any quote, not after, come three questions: the fuel that went in, its quantity, and whether it has run. That is why. The answers change a range into a straight figure.
About Upper Rissington, briefly
Upper Rissington is a village in Gloucestershire, situated in the Cotswold hills at an elevation of 232 metres. Upper Rissington lies near the villages of Little Rissington, Church Westcote, and Nether Westcote, and is approximately 20.9 miles from Oxford. Upper Rissington has a population of around 1026 residents, with a predominance of terraced housing. Upper Rissington is located inland, about 72.1 miles west of London.
Fuel drain cover across Gloucestershire, Upper Rissington included
Our teams answering petrol in diesel call-outs around Upper Rissington, in the GL postcode area, also work the locations around it, Little Rissington, Church Westcote and Nether Westcote among them. Our engineers drain wherever the vehicle is — your own driveway, a lay-by, a supermarket car park, a forecourt — so it never needs to come to us.
In Upper Rissington and still at the pump?
No position is better: that is where you now are. Keep it off. Call.