--- title: Explained: Petrol in a Diesel Car Westhill canonical: https://www.petrolinadieselcar.co.uk/petrol-in-diesel/westhill-aberdeenshire/ location: Westhill county: Aberdeenshire latitude: 57.153370 longitude: -2.276230 service: Petrol in a Diesel Car updated: 2026-10-21 --- # Should You Worry? Petrol in a Diesel Car in Westhill Far less than you probably are, provided it hasn't been started. Till your ignition primes the pump, the starter turns, or your car is driven, petrol in a diesel tank just waits there and does nothing. Which means the honest reply to that first Westhill question — "have I wrecked it?" — usually no. Leave your motor off and ring Petrol in Diesel — that is how you keep it that way. The remainder of this page covers 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? Passing through an engine, diesel does two things at once. It combusts, and before it ignites it protects. Designed to extremely fine clearances, your injectors and your pump rely on your diesel moving through them to stop their surfaces wearing against one another. Poorly at the first, not at all at the second: that is petrol. It is runnier than diesel and removes the lubrication the fuel system hinges on, and so a pump running on a petrol mixture is a pump wearing itself. And petrol is made to resist igniting under compression, which is the reverse of what a diesel needs from its fuel. That's where the clattering comes from. Taken together, they make clear the shape the problem takes. The harm is done by circulation, not by contact. Petrol in a tank is a fuel issue. The beginning of a mechanical problem is a pump that has been running on that petrol — and whatever a worn pump sheds moves on with your fuel to your injectors downstream. ## Four situations we see around Westhill: how bad is petrol in a diesel? Fuelled, and never started: nothing beats it. Just your tank has petrol in it, so the job is draining that tank and cleaning the fuel system where the car sits. This scenario can only really take place on a forecourt: anywhere else, your car got there by being driven. A moment's running, or just the ignition on. Once primed, the fuel system has drawn petrol out of your tank as far as the filter and the lines. Drain, flush, see to the filter: still usually simple. Driven a couple of miles. Now the pump has spent those miles running on weakened fuel. Distance is only half of that; how hard it was driven counts equally. Either way the work runs to the tank, your lines, the filter and fresh fuel through the whole system. Short trips, such as the school run to the local primary school, are one thing. A run as far as Aberdeen, under 10 miles away, is a very different task. So is any miles on the M90, over 50 miles from Westhill, where your engine has been working hard throughout. It protested, and only then stopped: smoke, rattling, a throttle gone soft, an idle gone ragged. That's the motor telling you its fuel has stopped acting like diesel. Pull up where you are — on the verge on Old Skene Road, at the kerb, down a side road — and don't move it. The drain and flush still go first, and they take care of it: when a vehicle is stopped quickly, lasting damage is very uncommon. ## Petrol in a diesel myths Westhill people hear "Top it up the rest of the way with diesel and it will be fine" — a myth. It will not. A bigger tank of the same mix is all you get, since topping up takes out nothing. Percentage isn't how a diesel fuel system copes with petrol, whatever that guidance supposes. "Current diesels can handle a little petrol" — a myth, and nearer the opposite. A modern diesel sends its fuel through finer components at higher pressure, which makes the lubrication count more, not less. "It starts, it drives, and so no harm done" — the myth that catches more motorists than any other. The motorist of a petrol motor fed diesel usually stops, since it will not run, and the harm stops there. Feed petrol to a diesel and it usually fires up, ticks over and pulls away like nothing happened — all while its pump wears. A running engine does not mean fine. Myth: "Add some two-stroke oil and drive it home." It's an old fix for a distinct issue. It doesn't put back what petrol has thinned, and the petrol is still in the tank after that. The next start sends petrol back round the pump from the lines and your filter, where some of it sits once the engine has run. That's why a DIY tank drain doesn't sort it — a myth. On top of that, petrol cleared into a can by the road is genuinely hazardous. ## Why petrol in a diesel happens so easily Nobody does it on purpose, and it is rarely carelessness. A diesel nozzle mostly won't fit a petrol vehicle, but the smaller petrol nozzle goes into the filler of a diesel nearly without resistance — so forecourts make this one mistake simple, and only in that direction. When habit and the car stop matching, it happens. Courtesy car, hire car, or a car that is brand new. A household with one petrol and one diesel on the driveway. A forecourt you know, only with its pumps arranged differently. Fuelling up in a hurry en route to Dyce, with a train to catch. Years of petrol motors behind you, a diesel Volkswagen Golf in front of you on the forecourt for its first tank — that's when. The 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 around Westhill: preventing petrol in a diesel - Not every forecourt in the UK keeps to green for unleaded and black for diesel, though most usually do. Read the petrol pump's label; the colour is only a clue. - Many cars state the fuel type inside your filler flap or on the cap, so check it on your first fill in any car you don't know. - Mark your key. In a household with one of each, a coloured fob or a sticker on your diesel's key does more than any amount of meaning to remember. - "Diesel", aloud, before you pick up the nozzle — every time a new or hired car needs its first tank. It seems silly. It works. - Thinking about something else is when this becomes an easy mistake to make, so tuck the phone away then keep your mind on the pump. - Some diesels have a filler built to refuse a petrol nozzle, and devices you can add are available for cars without one. Such an inhibitor helps up to a point — as a safety net, not a reason to stop reading the petrol pump. - Spotting it mid-fill? Stop at once. A weaker mixture results from less petrol in the tank, but the next stage stays the same: don't fire it up. ## Put petrol in a diesel in Westhill already? The order of things is short, then. Don't turn your ignition on, and don't start it. If you're still at the forecourt — Tesco or anywhere else — ask the staff to help you push the car away from the pump. Call 0333 366 0103 next, with three answers — your fuel, the rough quantity, and if it's run. Say so if it was AdBlue instead of petrol: it's a different problem, with its own page for Westhill, since AdBlue brings corrosion and deposits instead of lost protection. ## Westhill petrol in a diesel jobs: why one costs more than another A fair single quote does not exist here: four scenarios, four separate jobs. What shifts your cost is chiefly which of them you're in. Two things come after that: the petrol that went in as a proportion of what that tank holds, then the place the car is in and whether our van can get to it safely. Three questions come first, before any quote, instead of after — what went in, how much, has it run — and this is the reason. With the replies, you get a straight figure instead of a range. ## About Westhill, for a moment Westhill is a town in Aberdeenshire, situated inland at an elevation of 133 metres, approximately 6.8 miles west of Aberdeen. Westhill has a population of around 7178 people, with a predominance of detached housing. Westhill is close to several nearby communities, including Elrick, Kingswells, and Cairnie, and is located about 399.5 miles north of London. ## Across Aberdeenshire and around Westhill: fuel drain cover Petrol in diesel call-outs in Westhill — part of the AB postcode area — go to vans that also cover the places about it, Elrick, Kingswells and Cairnie included. The vehicle doesn't need to come to us: we drain on a forecourt, in a supermarket car park, in a lay-by or on your own drive. ## Still at the petrol pump in Westhill? The best position there is, then — that's where you are. Keep the vehicle switched off, and ring.