Petrol in a Diesel Car in Newhaven: How Worried Should You Be?
Not started? Then less worried than you probably are. Everyone in Newhaven begins with "have I wrecked it?", and the honest answer is usually no: petrol left in the tank of any diesel stays harmless until priming, cranking or driving draws it into your fuel system. Keep it like that: leave your engine off then call Petrol in Diesel. The remainder of this page sets out what petrol actually does to a diesel, how to tell 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?
Diesel does two tasks on its way through an engine. Before it combusts, it lubricates — and then it combusts. What stops the surfaces inside the high-pressure pump and the injectors from wearing against one another is your diesel flowing through them — they're designed to extremely fine tolerances.
Petrol handles the first task badly and the second not at all. Being less viscous than diesel, petrol strips out the lubrication a fuel system needs, so a pump on that mixture to wear itself. It's also made to resist igniting under compression — the opposite of what a diesel needs — which is why you hear the rattling.
Seen together, they make clear what shape the issue has. Contact doesn't do the harm — movement does. Petrol in a tank is a fuel problem. The beginning of a mechanical problem is a pump that has been labouring on that petrol — and whatever a worn pump sheds moves on with the fuel to your injectors downstream.
Petrol in a diesel around Newhaven: how bad is it? Four situations
Filled but never started — the best it gets. Being at a forecourt is what makes this possible: elsewhere, the vehicle has been driven there to begin with. With that petrol held in the tank alone, it's cleared and cleaned right where it stands, and nothing more is needed.
Started for a moment, or just the ignition on. Once primed, the system has pulled petrol from the tank up to the filter and your lines. Still generally simple: drain, flush, and the filter sorted.
The pump now spent a few miles on thinned fuel — that is what driving the car does. How hard the vehicle was driven matters as much as how far, and this work takes in the tank, your lines, your filter and fresh fuel through the whole circuit. Short trips, such as the school run to the local primary school, are one thing. A run as far as Edinburgh, under 3 miles away, is a very different job. So is any distance on the M8, under 10 miles from Newhaven, where your engine has been running hard throughout.
Driven on till it protested — knocking, smoke, an uneven idle, a dead throttle. The fuel is not acting like diesel any more, and your engine is saying so. Leave it wherever it has stopped: a lay-by, a side street, the verge on Peacock Court. The drain and flush still go first, and they take care of it: if a vehicle is stopped early, long-term damage is very unusual.
Newhaven motorists and that petrol in a diesel stories they hear
Myth: topping up to full with diesel makes it fine. It does not. Nothing is removed when you top up — the tank simply holds more of the same blend. That guidance supposes a diesel fuel system handles petrol by percentage. It does not.
Myth: "A current diesel can cope with a bit of petrol." If anything, the reverse. A modern diesel runs its fuel through finer parts at higher pressure, which makes the lubrication count more, not less.
Myth: "If it starts and drives, there's no damage done." This is the one that catches motorists. Any petrol engine fed diesel normally will not run, and so the motorist stops and the harm stops with them. Feed petrol to a diesel and it normally starts, ticks over and pulls away like nothing happened — all while its pump wears. Being able to run is not proof of being fine.
Myth: "Add some two-stroke oil and drive the vehicle home." It is an old fix for a different fault. None of what petrol weakened gets put back by it — and afterwards, your tank still holds the petrol.
Myth: "Drain the tank yourself and you're sorted." After the engine has been run, some of that petrol is no longer in your tank: it is in the filter and the fuel lines, and it goes straight back through the pump on your next start. Besides, petrol cleared into a can by the road is genuinely dangerous.
Why petrol in a diesel occurs at all
Nobody does it on purpose, and it is seldom carelessness. One way only, because of the nozzles: the slimmer petrol one slips inside a diesel filler with almost no resistance, whereas the diesel one mostly will not fit a petrol vehicle. That is how the forecourt makes it straightforward.
The moment routine stops matching the vehicle is the moment it occurs. Hire cars, courtesy cars, and cars that are new to you. A household with one petrol and one diesel on the drive. A well-known forecourt with the pumps in a different order. A rushed fill en route to Edinburgh Waverley with a train to catch. Years of petrol cars behind you, a diesel BMW 3 Series in front of you on the forecourt for its first tank — that's when. Your hand does what it has always done when you add rain, a phone call or a back seat full of children.
Preventing petrol in a diesel next time you fill up around Newhaven
- The label is what matters, and so check the pump instead of the colour: in the UK unleaded handles are normally green and diesel black, but not on each forecourt.
- Many vehicles state the fuel inside the filler flap or on the cap, and so check there on your first fill in any vehicle you do not know.
- One of each in the home? Label the key to the diesel — a coloured fob, a sticker — because meaning to remember isn't enough.
- It sounds silly and it does the trick: on the first fill in a new or hired car, say "diesel" aloud before you lift the nozzle off the pump.
- Thinking about something else is when this becomes an easy mistake to make, so tuck your phone away then keep your mind on the pump.
- Up to a point, a misfuel inhibitor helps: some diesels come with a filler built to reject a petrol nozzle, and aftermarket devices are available for the remainder. Treat it as a safety net, then keep checking the pump.
- The moment you notice, stop: less petrol inside your tank means a thinner mixture. What to do next does not change, though — still do not start it.
Newhaven: already put petrol in a diesel?
Short and simple, then, is the order of things. Leave it unstarted, with your ignition switched off too. Ask the attendants to help you push it away from the petrol pump if you are still on the forecourt, whether that's Asda or somewhere else. Then call 0333 366 0103 and tell us what went in, about how much, and whether it's run.
Corrosion and deposits are the issue with AdBlue, where petrol means lost lubrication. So if it was AdBlue, say so — and read its own Newhaven page.
One petrol in a diesel job in Newhaven costs more than another. Why?
Four separate jobs lie behind the four situations above — which is why there is no fair single quote. Chiefly, the cost shifts with which situation you're in. Where your car is counts too, and whether a technician can safely reach it, after the ratio of petrol to what that tank holds.
That's why our technicians ask three questions before pricing instead of after: what got in, how much, and whether it has run. Given the replies, you get a straight figure rather than a range.
About Newhaven, briefly
Newhaven is a coastal suburban area in the City of Edinburgh, situated approximately 1.9 miles from Edinburgh city centre. Newhaven sits on the Firth of Forth at a low elevation of around 11 metres, with its history and development influenced by its proximity to the sea. Newhaven is characterised by its predominantly flat-type housing and is located near other Edinburgh suburbs such as North Leith and Trinity.
Across City of Edinburgh and in Newhaven: fuel drain cover
North Leith, Trinity and Hamilton Wynd are among the locations around Newhaven that the same teams work, answering petrol in diesel call-outs across Newhaven's EH postcode area. You need not move your vehicle to us. Forecourts, supermarket car parks, lay-bys and your own driveway are all spots we drain.
Still at the pump in Newhaven?
The best position there is, then — that is where you are. Leave the car turned off, and ring.