Petrol in a Diesel Car in Stratton-on-the-Fosse: How Worried Should You Be?
If it hasn't been started, you can worry less than you probably are. Until your ignition primes your pump, your starter cranks, or the car is driven, petrol in a diesel tank simply rests there and does no harm. Which makes the truthful reply to that first Stratton-on-the-Fosse query — "have I ruined it?" — usually no. Leave your engine off then call Petrol in Diesel — that is how you keep it like that. Below, this page sets out what petrol really does inside a diesel, how far it might have got, and how to stop it happening to you a second time.
Inside your engine: what petrol in a diesel really does
Diesel does two jobs on its way through an engine. Before it ignites, it protects — then it burns. What stops the surfaces inside the high-pressure pump and the fuel injectors from wearing against one another is the diesel passing through them — they're designed to very fine tolerances.
Of those two jobs, petrol manages the first 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 that mixture to wear itself. It is also made to resist igniting under compression — the reverse of what a diesel needs — which is why you get the clattering.
The shape of the trouble is clear when you put those together. Not contact but circulation is what does the harm. All a tank with petrol in it amounts to is a fuel issue. After the pump has been working on that petrol, a mechanical issue has started: whatever is shed by a pump that is wearing travels downstream to the fuel injectors with the fuel.
Four situations our technicians see in Stratton-on-the-Fosse: how serious is petrol in a diesel?
The best case there can be: filled up, never started. Being at a forecourt is what makes this possible: elsewhere, the car has been driven there to begin with. With that petrol held inside the tank alone, it is drained and cleaned on the spot, and nothing more is needed.
A moment's running, or just the ignition on. With the fuel system primed, your lines and filter already hold petrol that came from that tank. Usually nothing more than draining, purging and sorting the fuel filter, and so still straightforward.
Driven a few miles. Now the pump has spent these miles labouring on weakened fuel. Tank, lines, filter, then clean fuel run through the whole system: that's the work, and the way the car was driven matters as much as the distance. On the school run to St Vigor & St John Church School, the distance is short. Driving as far as Wells, under 10 miles away, makes a very different job — as does any miles on the M32, under 15 miles from Stratton-on-the-Fosse, with the engine labouring hard all the way.
It protested, and only then stopped: smoke, clattering, a throttle gone soft, an idle gone ragged. What you are hearing is your motor reporting fuel that no longer behaves like diesel. Pull up where you are — on the verge on Church Lane, at the kerb, down a side road — and do not move it. A vehicle stopped early very seldom has permanent damage, since the drain and the flush-through, which still come first, sort it out.
Petrol in a diesel stories Stratton-on-the-Fosse motorists hear
Myth: topping up to full with diesel makes it fine. It doesn't. Nothing comes out when you top up — your tank just carries more of the same blend. The idea behind that advice — that diesel fuel systems accept petrol by percentage — is wrong.
Myth: "A modern diesel can cope with a bit of petrol." If anything, the reverse. At higher pressure, through smaller parts: that's how a current diesel moves its fuel, so the lubrication counts for more, not less.
"It starts, it drives, so no harm done" — the myth that catches most motorists than any other. Feed diesel to a petrol motor and it normally will not run, so the driver stops — and the damage stops with them. Feed petrol to a diesel and it normally fires up, ticks over and pulls away as if nothing has happened — all the while its pump is wearing. A running engine does not mean fine.
"A drop of two-stroke oil and drive it home" — a myth, taken from a fix from years ago, for a distinct problem. What petrol has diluted remains thinned, and the petrol remains in the tank regardless.
Myth: "Drain your tank yourself and you're sorted." Once the engine has been run, some of the petrol is no longer inside that tank: it is in your filter and the fuel lines, and it goes right back through your pump at your next start. Also, a can of petrol filled by the roadside is truly risky.
How does petrol in a diesel take place?
A careless moment is seldom the cause, and no one means to do it. The forecourt makes it easy: the petrol nozzle is the narrower of the two, and it slides into a diesel filler with almost no resistance, while a diesel nozzle generally will not go into a petrol car at all. So the error runs one way.
It occurs when routine and the vehicle stop matching. Any motor that is new to you — a hire car, on loan as a courtesy car, or brand new. One petrol and one diesel on the drive of the same household. Your normal forecourt, its pumps now in a different order. Filling up in a hurry on the way to Frome, with a train to catch. A new-to-you diesel Volkswagen Golf, its first fuelling, and a motorist accustomed to petrol: precisely when it occurs. Your hand does what it has always done once you add rain, a phone call or a back seat full of kids.
Next time you fill up in Stratton-on-the-Fosse: avoiding petrol in a diesel
- The label is what counts, and so check the pump rather than the colour: in the UK unleaded handles are usually green and diesel black, but not on every forecourt.
- Many motors state the fuel type inside your filler flap or on the cap, so check there on the first fill in a car you do not know.
- Label your key. In a household 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 leaves the pump the first time you fuel a hired or new car, say "diesel" out loud. Silly, perhaps, but it does the trick.
- Mistakes like this are straightforward to make while your mind is on something else, and so the phone goes away.
- Up to a point, a misfuel inhibitor helps: some diesels come with a filler designed to reject a petrol nozzle, and aftermarket devices are available for the remainder. Treat it as a safety net, then keep reading the pump.
- Stop the moment you notice. Less petrol inside the tank makes a weaker mix. It does not change what to do next, which is still not to crank it.
Put petrol in a diesel around Stratton-on-the-Fosse already?
Then, there is just a short order of things. Starting it is out, and so is switching on the ignition. If you're still on the forecourt — Texaco or anywhere else — ask the attendants to help you roll the vehicle away from the pump. What was put in, roughly how much, and whether it has run: tell us that when you call 0333 366 0103.
Corrosion and deposits are the trouble with AdBlue, where petrol means lost lubrication. So if it was AdBlue, say so — and read its own Stratton-on-the-Fosse page.
What makes one Stratton-on-the-Fosse petrol in a diesel task cost more than the next
Four different jobs lie behind the four situations above — which is why there is no honest single price. What shifts the cost is mostly which of them you are in. Beyond that it's the share — how much petrol got in against how much the tank holds — and after that where your car is and whether a technician can reach it safely.
That is why our engineers ask three questions before costing instead of after: what got in, how much, and if it's run. With those replies, there is a straight figure instead of a range.
About Stratton-on-the-Fosse and its setting
Stratton-on-the-Fosse is a small village in inland Somerset, situated near the city of Wells and close to the villages of Killings Knap, Barlake, and Chilcompton. Stratton-on-the-Fosse sits at an elevation of around 170 metres, with semi-detached housing being the predominant type of accommodation. Stratton-on-the-Fosse remains a quiet, rural community with a population of approximately 510 residents. Stratton-on-the-Fosse is located about 103 miles west of London, making it a relatively remote village in the South West region.
Across Somerset and in Stratton-on-the-Fosse: fuel drain cover
Stratton-on-the-Fosse rests in the BA postcode area, and our teams that answer petrol in diesel jobs there work the locations around it as well — Killings Knap, Barlake and Chilcompton among them. You need not bring the car to us. Forecourts, supermarket car parks, lay-bys and your own drive are all spots where we work.
In Stratton-on-the-Fosse and still at the pump?
Then you're in the best position there can be. Keep the vehicle turned off, and ring.