--- title: Worried? Petrol in a Diesel Car Old Town canonical: https://www.petrolinadieselcar.co.uk/petrol-in-diesel/old-town-east-sussex-tn40-2/ location: Old Town county: East Sussex latitude: 50.847450 longitude: 0.477130 service: Petrol in a Diesel Car updated: 2026-10-04 --- # Should You Worry? Petrol in a Diesel Car in Old Town If it hasn't been started, worry far less than you likely are. Petrol resting in a diesel tank does nothing to your engine until something pulls it through the fuel system — the ignition priming the pump, the starter, or the drive on its own. So the truthful answer to the first query everyone around Old Town asks, "have I wrecked it?", is generally no. Leave the motor off then phone Petrol in Diesel — that keeps it that way. Read on for three things: the effect petrol has inside a diesel engine, the signs of how far it has spread, and ways to make sure you never repeat it. ## Petrol in a diesel: what does it do to the engine? On its way through an engine, diesel has two tasks. It lubricates to begin with, and after that does it burn. Designed to very fine gaps, your injectors and the pump depend on your diesel flowing through them to keep their surfaces from wearing against one another. The second task petrol does not do at all, and the first it does badly. The rattling comes from petrol being made not to ignite when compressed, which is precisely the opposite 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 mixture is wearing itself. The shape of the issue is plain once you put those together. The harm is done by circulation, not by contact. All a tank with petrol in it amounts to is a fuel fault. Whatever a worn pump sheds travels on, carried by your fuel, into the injectors downstream, which is why a pump that has been working on the petrol is where a mechanical problem begins. ## Old Town, petrol in a diesel: four situations, from mild to major The best case there is: filled up, never started. At a forecourt, and really only there, the petrol is still limited to the tank — because everywhere else the car was driven to reach it. The task is draining and cleaning on the spot. The ignition turned on, or a short start. Once primed, your system has pulled petrol from your tank up to your filter and the fuel lines. Drain, flush, deal with the fuel filter: still normally straightforward. Those few miles on the road were your pump working on fuel diluted by petrol the whole way. The work is the tank, your lines, the fuel filter and clean fuel through the whole system, and how hard the vehicle was driven matters as much as how far. On the school run to Chantry Community Primary School, the mileage is small. Driving as far as Brighton and Hove, under 50 miles away, makes a very different job — as does any distance on the M20, under 50 miles from Old Town, with the motor labouring hard all the way. Knocking, a ragged idle, smoke, a throttle gone soft: driven until it complained. What you are hearing is your motor signalling fuel that no longer behaves like diesel. Whether it is the verge on Chantry Lane, a lay-by or a side road, stop where you are then leave it. A vehicle pulled over soon very rarely has long-term damage, as the drain and the flush, which still go first, sort it out. ## Petrol in a diesel myths Old Town motorists hear Myth: "Fill it the rest of the way with diesel and it'll be fine." It will not. A bigger tank of the same mixture is all you get, since topping up takes out nothing. That guidance assumes a diesel fuel system handles petrol by percentage. It does not. If anything, the opposite is true. Myth: "A newer diesel can cope with a bit of petrol." At higher pressure, through smaller parts: that's how a current diesel handles its fuel, so the protection matters more, not less. Myth: "If it starts and drives, there's no harm done." This is the one that fools motorists. A petrol motor fed diesel generally won't run, and so the driver stops and the harm stops with them. Nothing looks to have happened when a diesel fed petrol fires up, ticks over and drives away, which it usually will; meanwhile the pump grinds. Running is not the same as fine. Myth: "Add some two-stroke oil and drive the car home." It's an outdated workaround for a distinct issue. None of what petrol thinned is put back by it — and afterwards, that tank still contains that petrol. "Drain it yourself and you are sorted" — a myth, because after it's been running some petrol sits in the fuel filter and lines, waiting to go right back through your pump at the next start. Draining petrol into a can at the kerbside is also truly hazardous. ## How does petrol in a diesel occur? A careless moment is seldom the cause, and no one means to do it. A diesel nozzle mostly will not fit a petrol car, but the smaller petrol nozzle goes into the filler of a diesel almost without resistance — so forecourts make this one error easy, and just in that direction. Habit and your car falling out of step is how it takes place. A motor 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 driveway. A forecourt you know, but with its pumps arranged differently. Fuelling up in a rush en route to Bexhill, with a train to catch. Years of petrol vehicles behind you, a diesel Volkswagen Passat in front of you on the forecourt for its first tank — that's when. Throw in a back seat full of kids, a phone call or rain, and the hand wins. ## Next time you fill up in Old Town: preventing petrol in a diesel - Check the pump, not the colour. In the UK unleaded handles are generally green and diesel black, but not on every forecourt. The label is what counts. - The first fill in a strange vehicle is the time to check the filler flap — on it, or on the cap, plenty of motors state the fuel they take. - Good intentions count for less than a sticker or a fob in a vivid colour on the diesel's key when a home has one of each. So label it. - Before the nozzle leaves the petrol pump the first time you fuel a hired or new motor, say "diesel" out loud. Daft, perhaps, but it does the trick. - Put the phone away. This is an easy mistake to make while you are thinking about something else. - Some diesels have a filler designed to block a petrol nozzle, and devices you can add exist for cars without one. Such an inhibitor helps up to a point — as a backstop, not a reason to stop reading the pump. - As soon as you notice, stop: less petrol inside that tank makes a thinner blend. What to do next doesn't change, though — still don't start the vehicle. ## Petrol already in a diesel around Old Town? Begin here In that case, there's just a short order of things. Do not turn the ignition on, and do not crank it. The staff at the forecourt — whether at BP itself or wherever you filled up — will normally help roll it clear of the petrol pump if you ask. Then phone 0333 366 0103 and tell us what went in, about how much, and whether it has run. AdBlue, not petrol? Then say so. Corrosion and deposits, not lost protection, make it a separate fault — Old Town has a page all for it. ## Why one petrol in a diesel job around Old Town costs more than another The four situations above are four different tasks, so no single price for this would be honest. What moves your cost is mostly which of them you're in. After that it's the ratio — how much petrol was put in against how much the tank holds — and then where the car is and whether a van can get to it safely. Three questions come first, before quoting, instead of after — what got in, how much, has it run — and that is the reason. Given the replies, there is a straight figure rather than a range. ## About Old Town, for a moment Old Town is a coastal suburban area in East Sussex, situated near the town of Bexhill-on-Sea and approximately 27 miles from Brighton and Hove. Old Town sits at an elevation of around 33 metres, with its predominant housing stock consisting of flats. Old Town is part of the larger Bexhill-on-Sea urban area, which also includes nearby Sidley and Bexhill. Old Town is located within the South East region of England, about 52 miles from London. ## Old Town and East Sussex: where our fuel drain cover runs The teams answering petrol in diesel call-outs in Old Town, in the TN postcode area, equally work the locations around it, Bexhill-on-Sea, Bexhill and Sidley included. A forecourt, a supermarket car park, a lay-by or your own driveway are all spots we drain, and your car doesn't need to come to us. ## Old Town: still at the petrol pump? Nothing beats it: that's where you are. Turned off it stays; then phone.