--- title: Worried? Petrol in a Diesel Car Eddington canonical: https://www.petrolinadieselcar.co.uk/petrol-in-diesel/eddington-cambridgeshire/ location: Eddington county: Cambridgeshire latitude: 52.218670 longitude: 0.084280 service: Petrol in a Diesel Car updated: 2026-10-04 --- # Petrol in a Diesel Car in Eddington: How Worried Should You Be? Likely less than you are now — as long as nobody has started the car. Till your ignition primes the pump, the starter cranks, or your vehicle is driven, petrol in a diesel tank simply sits there and does no harm. Which means the truthful reply to the first Eddington question — "have I wrecked it?" — usually no. Petrol in Diesel is who to ring, with the motor kept off, so it remains that way. Below, this page sets out what petrol actually does inside a diesel, how far it might have gone, and how to stop it happening to you a second time. ## What petrol in a diesel does to the motor Diesel does two tasks on its way through a motor. Oiling comes before burning; it does both. Very fine tolerances are built into your injectors and the high-pressure fuel pump, and only the diesel flowing through stops those surfaces grinding together. Petrol handles the first task poorly and the second not at all. The rattling comes from petrol being made not to ignite when compressed, which is precisely the reverse of what a diesel needs. On top of that it is runnier than diesel, it strips away the protection your system rests on, and any pump working on such a mixture is wearing itself. Put these together and the shape of the problem is plain. Contact doesn't do the harm — circulation does. Any tank with petrol in it is a fuel issue. After the pump has been working on that petrol, a mechanical problem has started: whatever is shed by a pump that's wearing is carried downstream to the fuel injectors with the fuel. ## Petrol in a diesel around Eddington: how bad is it? Four cases Fuelled, and never started: no case is better. Just your tank has petrol in it, and so the job is clearing that tank and rinsing the fuel system where the vehicle stands. This scenario can only truly take place at a forecourt: anywhere else, the vehicle got there by being driven. The ignition switched on, or a short start. With the fuel system primed, the lines and filter now contain petrol that has come from your tank. That's normally still a straightforward task — a drain, a flush, and your filter seen to. The pump has spent a few miles on thinned fuel — that is what driving the vehicle meant. The work is your tank, the lines, your filter and fresh fuel through the entire circuit, and how hard your car was driven matters as much as how far. Driving the kids to University of Cambridge Primary School is one sort of trip. Any distance on the M11, under a mile from Eddington, means your engine has worked hard throughout, and a run to Cambridge, under 3 miles away, makes a very different task as well. Driven on till it complained — knocking, smoke, a lumpy idle, a dead throttle. The engine is telling you your fuel is no longer acting like diesel. Pull up on the spot — on the verge on Turing Way, at the kerb, down a side road — and do not move it again. A vehicle stopped soon very rarely has long-term damage, as the drain and the flush, which still come first, deal with it. ## What Eddington 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 will be fine" — a myth. It won't. Nothing is removed by topping up — you're left with a fuller tank, still the same mixture. A diesel fuel system doesn't tolerate petrol by percentage in the way that guidance presumes. "Newer diesels can handle a little petrol" — a myth, and nearer the reverse. Finer components and higher pressure are the way a newer diesel runs its fuel, and that makes the lubrication matter more, not less. "It starts, it drives, so there is no harm" — the myth that catches more motorists than any other. Any petrol motor fed diesel normally won't run, and so the driver stops and the harm stops with them. While the pump grinds, a diesel fed petrol normally starts, ticks over and drives away as if nothing has happened. Fine and running are not the same thing. An old fix for a distinct fault lies behind this one. Myth: "Add some two-stroke oil and drive it home." It does not put back what petrol has diluted, and the petrol is still inside that tank after that. The next start draws petrol back round the pump out of your lines and your filter, where some of it sits after the engine has been run. That is why draining the tank yourself does not sort it — a myth. And, a can of petrol drained by the kerbside is truly hazardous. ## How petrol ends up: petrol in a diesel Nobody does it on purpose, and it's rarely carelessness. One way only, since of the nozzles: the smaller petrol one slips inside a diesel filler with almost no resistance, whereas the diesel one mostly won't fit a petrol vehicle. That's how the forecourt makes it simple. The moment habit stops matching the car is the moment it occurs. Any vehicle that's new to you — hired, on loan as a courtesy car, or just bought. A household with one petrol and one diesel on the drive. A forecourt you know, but with its pumps arranged differently. Rushing for a train outside Cambridge and filling up en route. Years of petrol cars behind you, a diesel Volkswagen Golf in front of you at the forecourt for its first tank — that is when. Throw in a back seat full of kids, a phone call or rain, and habit wins. ## Eddington motorists: how to avoid petrol in a diesel next time - Not every forecourt in the UK follows green for unleaded and black for diesel, even if most generally do. Check the petrol pump's label; the colour is only a hint. - In a car you don't know, look inside the flap over the filler or at the cap before your first fill: plenty of cars print the fuel there. - A coloured fob or a sticker on the diesel's key does more than any amount of meaning to remember, in a house with one of each. - "Diesel", aloud, before you pick up the nozzle — each time a new or hired car gets its first tank. It sounds daft. It does the trick. - Put the phone away. This is an easy mistake to make whilst you are thinking about something else. - Up to a point, a misfuel inhibitor helps: some diesels come with a filler built to reject a petrol nozzle, and aftermarket devices exist for the rest. Treat it as a safety net, then keep reading the petrol pump. - Stop as soon as you realise. Less petrol in the tank means a thinner blend. It does not change what to do next, which is still not to start the vehicle. ## Already put petrol in a diesel around Eddington? Then the order of things is short. Don't fire it up, and don't switch your ignition on. Ask the attendants to help you push it away from the pump if you are still on the forecourt, whether that is BP or somewhere else. Ring 0333 366 0103 next, with three facts — your fuel, the rough amount, and whether it has run. AdBlue, not petrol? Then tell us. Corrosion and deposits, not lost protection, make it a different fault — Eddington has a page just for it. ## What makes one Eddington petrol in a diesel job cost more than the next The four situations above are four different jobs, so no single price for this would be fair. What shifts the cost is chiefly which of them you're in. After that it is the ratio — how much petrol got in against how much the tank holds — and then where your car is and whether a technician can get to it safely. Three questions come first, before quoting, instead of after — what went in, how much, has it run — and this is the reason. A range turns into a straight figure when those replies are in. ## About Eddington, briefly Eddington is a suburban area located near Cambridge in Cambridgeshire, sitting at an elevation of around 20 metres. Eddington is close to several nearby places, including Ridgeway Village, High Cross, and Coton, and is about 1.8 miles from Cambridge. Eddington has a population of approximately 1495 people and predominantly consists of flat housing. ## Fuel drain cover in Eddington and across Cambridgeshire Eddington sits in the CB postcode area, and the vans that answer petrol in diesel calls there work the spots near it as well — Ridgeway Village, High Cross and Coton among them. No need to move your car to us. Forecourts, supermarket car parks, lay-bys and your own drive are all spots we drain. ## At the pump in Eddington, right now? Then, you could not be in a better place. Keep the car switched off, and ring.