--- title: Worried? Petrol in a Diesel Car Littlewick canonical: https://www.petrolinadieselcar.co.uk/petrol-in-diesel/littlewick-surrey/ location: Littlewick county: Surrey latitude: 51.326080 longitude: -0.598600 service: Petrol in a Diesel Car updated: 2026-10-11 --- # Petrol in a Diesel Car in Littlewick: How Worried Should You Be? If it hasn't been started, you can worry less than you probably are. Until your ignition primes the pump, your starter cranks, or your car is driven, petrol in a diesel tank simply waits there and does nothing. Which means the truthful reply to the first Littlewick question — "have I ruined it?" — usually no. Petrol in Diesel is who to phone, with the engine left off, so it stays that way. Read on for three things: the effect petrol has inside a diesel motor, the clues of how far it has got, and ways to make sure you don't repeat it. ## Inside the motor: what petrol in a diesel really does Passing through a motor, diesel does two jobs at once. Before it burns, it lubricates — and then it burns. Made to very fine tolerances, the injectors and your pump rely on the diesel moving through them to keep their surfaces from wearing against one another. The second task petrol doesn't do at all, and the first it does badly. A pump running on a petrol mixture is wearing itself out, because petrol is thinner than diesel and takes away the lubrication your fuel system depends on. Petrol is also designed to resist igniting under compression — the reverse of what a diesel needs from its fuel — and that is where the clattering comes. The shape of the trouble is plain when you put those together. Contact doesn't do the harm — movement does. Where that petrol is only in the tank, it's an issue of fuel, nothing more. After your pump has been labouring on that petrol, a mechanical fault has started: anything shed by a pump that is wearing is carried onward to the injectors with the fuel. ## Littlewick, petrol in a diesel: four cases, from mild to serious The best case there can be: filled up, never started. On a forecourt, and truly only there, that petrol is still limited to the tank — since everywhere else the car was driven to get to it. The job is emptying and purging on the spot. Started for a second, or only your ignition on. Once primed, the system has pulled petrol from your tank up to your filter and the lines. Drain, flush, see to the fuel filter: still usually simple. Some miles driven, and the pump has spent each of them running on thinned fuel. How hard your car was driven matters as much as how far, and the work takes in that tank, your lines, the filter and clean fuel through the whole system. A school run to Beaufort Primary School is one thing. Driving as far as Westminster, under 25 miles away, makes a very different task — as does any mileage on the M3, under 5 miles from Littlewick, with the engine working hard the whole time. Rattling, an uneven idle, smoke, a throttle gone soft: driven till it complained. The fuel is not behaving like diesel any more, and your engine is telling you. Stop wherever you are — the verge on Weasdale Court, a lay-by, a side street — and leave the vehicle where it is. Long-term damage is very uncommon when a car is stopped soon, and the fuel drain and flush-through that still come first deal with it. ## Petrol in a diesel myths Littlewick drivers hear False: topping up to full with diesel makes it fine. It doesn't. A bigger tank of the same mixture is all it gives, since topping up takes out nothing. Percentage is not how a diesel fuel system copes with petrol, whatever that advice supposes. "Modern diesels can handle a little petrol" — a myth, and nearer the reverse. A current diesel sends its fuel through finer components at higher pressure, which makes the lubrication count more, not less. The myth that catches drivers off guard: if it starts and drives, it must be unharmed. A petrol motor fed diesel normally will not run, and so the driver stops and the damage stops with them. Whilst your pump wears, a diesel fed petrol normally starts, ticks over and drives away as though nothing has happened. Running isn't the same as fine. Myth: "Add some two-stroke oil and drive the car home." It is an outdated fix for a distinct issue. It does not put back what petrol has weakened, and that petrol is still in that tank later. Myth: "Drain your tank yourself and you are sorted." After the motor has run, some of that petrol is no longer inside that tank: it's in the filter and your lines, and it goes right back through your pump on your next start. It is also really hazardous to drain petrol into a can by the roadside. ## Why petrol in a diesel takes place at all It's rarely carelessness, and no one does it on purpose. One way only, because of the nozzles: the narrower petrol one slips inside a diesel filler with almost no resistance, whereas the diesel one generally won't fit a petrol motor. That's how the forecourt makes it straightforward. When habit and the vehicle stop matching, it occurs. Hire cars, courtesy cars, and motors that are new to you. One petrol and one diesel on the driveway of the same household. A forecourt you know, but with its pumps laid out differently. Filling up in a rush en route to Woking, with a train to catch. Precisely the moment it happens: after years of driving petrol, a driver fills a diesel Volkswagen Golf for the first time. Throw in rain, a phone call or a back seat full of children, and your hand does what it has always done. ## Littlewick drivers: how to avoid petrol in a diesel next time - 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. - In a motor you don't know, look inside the flap over your filler or at the cap before the first fill: plenty of cars state the fuel there. - One of each in the household? Label your key to the diesel — a coloured fob, a sticker — since meaning to remember isn't enough. - "Diesel", out loud, before you pick up the nozzle — each time a new or hired car needs its first tank. It seems daft. It works. - Mistakes like this are easy to make whilst your mind is on something else, and so the phone goes away. - Up to a point, a misfuel inhibitor helps: some diesels come with a filler designed to refuse a petrol nozzle, and add-on devices are available for the remainder. Treat it as a safety net, then keep checking the pump. - Stop as soon as you realise. Less petrol in your tank means a thinner mix. It doesn't change what to do next, which is still not to crank it. ## Littlewick: already put petrol in a diesel? Short and simple, then, is the order of things. Starting it is out, and so is switching on the ignition. Ask the attendants to help you roll it clear of the petrol pump if you're still at the forecourt, whether that's BP or somewhere else. Call 0333 366 0103 next, with three facts — the fuel, the rough volume, and if it's run. Say so if it was AdBlue instead of petrol: it's a different problem, with its own page for Littlewick, because AdBlue brings corrosion and deposits rather than lost protection. ## One petrol in a diesel job in Littlewick costs more than another. Why? The four scenarios above are four separate tasks, so no single price for this would be honest. Which of them you are in is chiefly what shifts your cost. The proportion counts next, meaning how much of that tank is petrol, followed by the location of your car and whether reaching it is safe for our van. Before any quote, not after, come three queries: the fuel that was put in, the amount, and whether it has run. That's why. Given those answers, there is a straight figure instead of a range. ## About Littlewick Littlewick is a suburban area in Surrey, situated lakeside with an elevation of 28 metres, and is located approximately 23.8 miles from London. Littlewick has a mix of housing types, but is predominantly characterised by terraced homes. Littlewick is close to nearby places such as Horsell Birch, Whitfield Court, and Knaphill, and is part of the wider South East region. ## Across Surrey and around Littlewick: fuel drain cover Petrol in diesel call-outs around Littlewick — part of the GU postcode area — go to vans that also cover the places around it, Horsell Birch, Whitfield Court and Knaphill among them. The car doesn't need to move to us: our technicians drain at a forecourt, in a supermarket car park, in a lay-by or on your own drive. ## Still at the petrol pump in Littlewick? In that case, you couldn't be in a better position. Leave the car switched off, then ring.