Petrol in a Diesel Car in Upper Tysoe: How Worried Should You Be?
Probably less than you are now — as long as no one has started the vehicle. Everyone in Upper Tysoe begins with "have I wrecked it?", and the fair answer is normally no: petrol resting in your tank of any diesel stays harmless until priming, cranking or driving draws it into your fuel system. Leave your engine off and ring Petrol in Diesel — that is how you keep it like that. Below, you will find 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 the engine
Two jobs fall to diesel on its route through a motor. It lubricates to begin with, and after that does it burn. The high-pressure pump and your injectors are built to extremely fine tolerances, and your diesel passing through them is what stops those surfaces from grinding against one another.
Badly at the first, not at all at the second: that is petrol. A pump working on a petrol blend is wearing itself out, since petrol is thinner than diesel and strips out the lubrication the fuel system relies on. Petrol is also designed to resist igniting under compression — the opposite of what a diesel needs from its fuel — and that's where any clattering comes.
Put these together and the shape of the trouble is clear. The damage is done by movement, not by contact. Where that petrol is only in your tank, it is an issue of fuel, nothing more. Whatever a worn pump sheds goes on, borne by your fuel, into the fuel injectors further along, which is why a pump that has been working on that petrol is where a mechanical fault starts.
Four situations our engineers see around Upper Tysoe: how bad is petrol in a diesel?
Fuelled but never started — as good as it gets. That petrol is inside your tank and only your tank, and the job is a drain and a flush where your car stands. This is the one situation that can only really take place on a forecourt, as anywhere else the car has been driven to get there.
A brief spell of running, or just the ignition on. Once primed, your system has pulled petrol out of that tank as far as the fuel filter and your lines. Normally little more than emptying, purging and sorting the filter, and so still simple.
Those few miles driven meant your pump labouring on fuel weakened by petrol throughout. The work is that tank, the lines, your filter and fresh fuel through the entire system, and how hard the car was driven counts as much as how far. On the school run to Tysoe CofE Primary School, the distance is short. Very different a second time: a trip to Coventry, under 25 miles away, or some mileage on the M40, under 10 miles from Upper Tysoe, where the motor never stopped working hard.
It complained, and only then stopped: smoke, knocking, a throttle gone soft, an idle gone lumpy. The fuel isn't acting like diesel any more, and your engine is telling you. Stop where you are — on the verge on Walnut Pladdocks, at the kerb, down a side road — and do not move it again. What comes first is still the fuel drain and flush, and that takes care of it, with long-term damage very unusual if a vehicle is stopped quickly.
What Upper Tysoe people get told about petrol in a diesel — and the stories in it
"Top it up the rest of the way with diesel and it will be fine" — a myth. It won't. Topping up takes out nothing; it gives you a fuller tank of the same mix. A diesel fuel system doesn't accept petrol by percentage in the way that guidance supposes.
If anything, the reverse is true. Myth: "A current diesel can cope with a bit of petrol." Finer components and higher pressure are how a newer diesel runs its fuel, and that makes the protection count more, not less.
Myth: "If it starts and drives, there's no damage done." This is the one that catches people. Feed diesel to a petrol engine and it generally won't run, and so the driver stops — and the harm stops with them. Feed petrol to a diesel and it normally starts, ticks over and drives away like nothing happened — all while its pump wears. A running engine doesn't mean fine.
"A drop of two-stroke oil and drive it home" — a myth, borrowed from a fix from years ago, for a distinct issue. What petrol has thinned remains thinned, and that petrol remains in the tank anyway.
If the motor has run, part of that petrol sits in the fuel filter and the fuel lines, not that tank — and your next start pulls it straight back through the pump. So the myth "drain that tank yourself and you are sorted" does not hold. And, a can of petrol drained by the roadside is genuinely dangerous.
How petrol ends up: petrol in a diesel
No one does it on purpose, and it is seldom carelessness. One way only, because of the nozzles: the slimmer petrol one slides inside a diesel filler with almost no resistance, whereas the diesel one mostly will not fit a petrol motor. That is how the forecourt makes it simple.
Habit and the car getting out of step is how it happens. A new vehicle, a hire car or a courtesy car. Two motors on one drive, one petrol, one diesel. Your normal forecourt, its pumps suddenly in a different order. A hurried fill on the way to Banbury with a train to catch. Years of petrol cars behind you, a diesel Skoda Octavia in front of you on the forecourt for its first tank — that's when. Add a back seat full of children, a phone call or rain, and the hand takes over.
Avoiding petrol in a diesel next time you fill up in Upper Tysoe
- Green for unleaded and black for diesel is normal in the UK — but not on every forecourt. Go by the label on the pump, not the colour.
- The first fill in an unfamiliar motor is the time to check your filler flap — inside it, or on the cap, plenty of vehicles state which fuel to use.
- Mark 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 meaning to remember.
- Say it before you lift it. On the first fill in a new or hired car, say "diesel" aloud before you lift the nozzle off the pump. It seems daft and it works.
- Thinking about something else is when this becomes an easy mistake to make, so put your phone away and keep your mind on the pump.
- A misfuel inhibitor helps, up to a point. Some diesels come with a filler designed to reject a petrol nozzle, and add-on devices exist for cars without one. They are a safety net, not a reason to stop checking the petrol pump.
- As soon as you notice, stop: less petrol in that tank means a thinner mixture. What to do next does not change, though — still do not fire it up.
Upper Tysoe: already put petrol in a diesel?
The order of things is short, then. Starting it is out, and so is turning on the ignition. If you're still on the forecourt — The Forge Garage or anywhere else — ask the staff to help you push the car away from the pump. Next, 0333 366 0103. We'll ask what went in, roughly how much, and if it has been run.
AdBlue, not petrol? Then tell us. Corrosion and deposits, not lost protection, make it a separate issue — Upper Tysoe has a page just for it.
Upper Tysoe petrol in a diesel tasks: why one costs more than another
An honest single quote doesn't exist here: four scenarios, four separate jobs. Chiefly, the cost moves with which situation you're in. The ratio matters next, meaning how much of that tank is petrol, followed by the position of the car and whether getting to it is safe for a van.
What went in, how much, and whether it's run — three questions our engineers ask before quoting, not after, for precisely that reason. The replies turn a range into a straight figure.
About Upper Tysoe
Upper Tysoe is a small village in Warwickshire, situated inland at an elevation of 119 metres, with semi-detached housing being the predominant type of accommodation. Upper Tysoe lies near the villages of Middle Tysoe and Lower Tysoe, as well as the historic estate of Compton Wynyates. Upper Tysoe is located approximately 22 miles from Coventry and 71 miles from London, making it a rural community with some access to larger urban areas. Upper Tysoe has a population of around 584 people, living in a quiet inland setting.
Fuel drain cover across Warwickshire, Upper Tysoe included
Our teams answering petrol in diesel calls around Upper Tysoe, in the CV postcode area, also work the locations near it, Middle Tysoe, Lower Tysoe and Compton Wynyates among them. No need to bring your car to us. Forecourts, supermarket car parks, lay-bys and your own driveway are all locations we drain.
Upper Tysoe: still at the petrol pump?
No position is better: that's where you are. Switched off it remains; then call.