--- title: Comeytrowe: Petrol in a Diesel Car, Explained canonical: https://www.petrolinadieselcar.co.uk/petrol-in-diesel/comeytrowe-somerset/ location: Comeytrowe county: Somerset latitude: 51.002210 longitude: -3.128420 service: Petrol in a Diesel Car updated: 2026-10-28 --- # How Worried Should You Be? Petrol in a Diesel Car in Comeytrowe Unstarted? Then less worried than you likely are. Until the ignition primes the pump, the starter turns, or your vehicle is driven, petrol in a diesel tank just rests there and does nothing. Which makes the truthful reply to the first Comeytrowe query — "have I ruined it?" — normally no. To leave it like that, ring Petrol in Diesel then leave the motor switched off. The rest 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. ## What petrol in a diesel does to the motor On its way through a motor, diesel has two jobs. It lubricates first, and only then does it burn. Your high-pressure pump and your injectors are made to very fine gaps, and the diesel passing through them is what keeps those surfaces from grinding against each other. Petrol does the first job badly and the second not at all. The knocking comes from petrol being designed not to ignite when compressed, which is exactly the reverse of what a diesel needs. On top of that it is thinner than diesel, it strips out the lubrication your system depends on, and any pump working on such a mix is wearing itself. Seen together, they show the shape the issue takes. Not contact but movement is what causes the damage. Petrol in the tank is a fuel issue. A pump that has been running on that petrol is the beginning of a mechanical one, and whatever a worn pump sheds moves on with your fuel to the injectors further on. ## Four situations we see around Comeytrowe: how serious is petrol in a diesel? The best case there can be: filled up, not once started. Being at a forecourt is what makes this possible: elsewhere, the car has been driven there to begin with. With the petrol held inside that tank alone, it is emptied and flushed right where it stands, and nothing more is needed. Ignition on, or started for a second. Once primed, your system has drawn petrol out of your tank up to the filter and your lines. Drain, flush, see to the filter: still usually easy. Those few miles driven meant your pump working on fuel weakened by petrol throughout. Tank, lines, filter, then fresh fuel put through the entire circuit: that's this work, and the way the vehicle was driven counts as much as the miles. On the school run to Orchard Grove Primary School, the mileage is small. A run as far as Wells, under 50 miles away, is a very different job. So is any mileage on the M5, under 3 miles from Comeytrowe, where the engine has been working hard the whole time. Clattering, an uneven idle, smoke, a throttle gone soft: driven till it complained. The engine is telling you the fuel is no longer behaving like diesel. Leave it wherever it has stopped: a lay-by, a side street, the verge on Hine Road. What comes first is still the fuel drain and flush-through, and that takes care of it, with permanent damage very uncommon if a car is pulled over soon. ## What Comeytrowe people get told about petrol in a diesel — and the myths in it It will not be fine. The myth: "Fill it the rest of the way with diesel and it will be." Nothing is removed by topping up — you are left with a bigger tank, still the same mix. Percentage is not how a diesel fuel system tolerates petrol, whatever that advice supposes. If anything, the reverse holds. Myth: "A newer diesel can cope with a bit of petrol." A modern diesel sends its fuel through finer components at higher pressure, which makes the lubrication matter more, not less. "It starts, it drives, and so there is no harm" — the myth that trips up more drivers than any other. A petrol engine fed diesel generally will not run, and so the motorist stops and the damage stops with them. Feed petrol to a diesel and it normally fires up, ticks over and pulls away as if nothing happened — all while its pump wears. Being able to run isn't proof of being fine. Myth: "Add some two-stroke oil and drive the car home." It is an old workaround for a different issue. What petrol has weakened stays thinned, and that petrol remains in that tank anyway. "Drain it yourself and you're sorted" — a myth, because after it has been running some petrol sits in the fuel filter and lines, ready to go right back through your pump on your next start. Clearing petrol into a can at the kerbside is also really dangerous. ## Why petrol in a diesel occurs so easily Nobody does it on purpose, and it is rarely carelessness. One way only, since of the nozzles: the slimmer petrol one slides inside a diesel filler with almost no resistance, while the diesel one mostly will not fit a petrol vehicle. That is how the forecourt makes it straightforward. The moment habit stops matching the car is the moment it occurs. Courtesy car, hire car, or a car that is new. Households running one of each, petrol and diesel. A familiar forecourt with the pumps in a different order. A hurried fill on the way to Taunton with a train to catch. A new-to-you diesel Volkswagen Golf, its first fuelling, and a driver used to petrol: exactly when it happens. Throw in rain, a phone call or a back seat full of children, and the hand repeats what it has always done. ## Comeytrowe drivers: how to avoid petrol in a diesel next time - The label is what counts, and so check the pump rather than the colour: in the UK unleaded handles are normally green and diesel black, yet not on each forecourt. - In a car you don't know, look inside the flap over the filler or at the cap before the first fill: many vehicles state the fuel there. - Mark the key. In a house with one of each, a coloured fob or a sticker on the diesel's key does more than any amount of meaning to remember. - It sounds daft and it does the trick: on the first fill in a new or hired car, say "diesel" aloud before you take the nozzle off the pump. - Mistakes like this are straightforward to make whilst your mind is on something else, so the phone goes away. - Some diesels come with a filler designed to refuse a petrol nozzle, and devices you can add exist for motors without one. Such an inhibitor helps up to a point — as a safety net, not a reason to stop reading the pump. - Noticing it halfway? Stop there and then. A weaker mix results from less petrol in that tank, yet the next step stays the same: do not crank it. ## Already put petrol in a diesel in Comeytrowe? Then the order of things is brief. Starting it is out, and so is turning on your ignition. The attendants on the forecourt — whether at Texaco itself or wherever you filled up — will usually help roll it clear of the pump if you ask. Next, 0333 366 0103. We'll ask what got in, roughly how much, and if it's been run. Corrosion and deposits form the issue with AdBlue, where petrol means lost lubrication. So if it was AdBlue, say so — and read its own Comeytrowe page. ## What makes one Comeytrowe petrol in a diesel job cost more than the next The four scenarios above are four separate tasks, so no single quote for this would be fair. Chiefly, your cost shifts with which one you're in. Two things come after that: the petrol that was put in as a proportion of what the tank takes, then the spot your car is in and whether a technician can reach it safely. What was put in, how much, and if it's run — three questions we ask before costing, not after, for exactly that reason. With the answers, you get a straight figure rather than a range. ## About Comeytrowe and where it is Comeytrowe is a suburban area situated on the riverside in Somerset, with a relatively low elevation of 33 metres. Comeytrowe lies near several other local places, including Galmington, Sherford, and Trull, and is around 25 miles from the city of Wells. Comeytrowe has a population of approximately 4194 people, predominantly living in semi-detached housing. Comeytrowe is also located at a distance of around 134 miles from London, making it a commuter-friendly location. ## Comeytrowe and Somerset: where our fuel drain cover reaches Galmington, Sherford and Trull are among the places around Comeytrowe that the same teams work, answering petrol in diesel calls across Comeytrowe's TA postcode area. The car doesn't need to move to us: we drain on a forecourt, in a supermarket car park, in a lay-by or on your own driveway. ## Still at the petrol pump around Comeytrowe? Then you're in the best spot there is. Leave the car switched off, then ring.