--- title: Drain Petrol From a Diesel Car — Goar Knap canonical: https://www.petrolinadieselcar.co.uk/petrol-in-diesel/goar-knap-somerset/ location: Goar Knap county: Somerset latitude: 50.946080 longitude: -2.620040 service: Petrol in a Diesel Car updated: 2026-10-11 --- # Put Petrol in a Diesel Car in Goar Knap? With that tank still carrying the fuel and the motor not yet started, almost every job requires only a drain, so leave your engine off. That outcome is settled in the minutes straight after filling up, rather than by the amount that was put in. Across Goar Knap and the rest of Somerset, Petrol in Diesel drains the car and cleans it where it stands, whether at a roadside, on a driveway or at a forecourt. One call our way will be enough: our team will show you what happens next. Make that right away. ## Your first five minutes: petrol in a diesel - As you drive, your pump and the fuel injectors suffer. That's why you do not start the vehicle, and why you do not depend on it once it has started. The catch about petrol in a diesel specifically — the point people get wrong — is that it drives away happily for the first mile or two. Diesel in a petrol engine typically can't run at all, which stops the motorist and stops the damage with them. This one lets you carry on. - Two jobs, diesel: it ignites, and on the way through it keeps your high-pressure fuel pump and injectors greased. Petrol only does the one. That is why the ignition remains off also — flick it on and you commonly prime your system, and that's petrol leaving the tank for just those parts. - Topping up gets rid of nothing. It gives you a larger tank of the same mixture, because a diesel fuel system won't accept petrol by percentage in the way that guidance implies — so don't add diesel on top to weaken it. Grade is immaterial too: super unleaded is petrol. - A motor that hasn't shifted is the easiest one to sort, so remain where you are if you safely can. Stopped on the verge on Matthews Road? Hazards on, and keep the vehicle there. An odd place suits us better than a started motor. - Have your position ready before you call. A postcode starting BA21 4 and whatever is next to you with a sign on it is the difference between the van arriving and our van circling. - What went in, about how much, and whether the engine has fired — the three facts shape the full visit. Phone 0333 366 0103 and tell us. Ring us before you collect the vehicle. Petrol into a diesel Volkswagen Passat this morning, and it at Yeovil Pen Mill ever since? Then the wait has taken nothing from you: fuel in a tank is dormant, and any harm came on the run in, when the pump was pulling diesel that petrol had weakened. ## At a forecourt: removing petrol from a diesel A big chunk of the work is completed at the pump, since that is where it mostly starts. The drain usually happens there and then. Still on the forecourt at Esso? Given the site's agreement, that is a spot we work, and often. At the forecourt, the mistake is caught with your engine never run, and no place else manages it. Everywhere else — a car park, a driveway, a lay-by — the car was started and driven to get there, which means fuel was drawn from the tank, through your filter then into the high-pressure pump. That is not a disaster, and we can still deal with it where it stands. It does mean your lines and your filter need cleaning as well as your tank, and that's settled by the few seconds between seeing the till receipt and going for the keys. The staff will normally help you push it out from the petrol pump so the next motorist can get past. That is worth doing. Four car lengths isn't worth a restart. The call our engineers hope for runs like this: diesel Nissan Qashqai, a few litres of unleaded, done a couple of miles, now turned off outside Aldi. What we are truly asking is how much fuel your pump has pulled — not how long ago it was. ## Do we serve your side of Goar Knap? These same rounds bring us to New Town, Pen Mill, Crofton Park, Little Lyde and Yeovil along with Goar Knap, which is a residential suburb. If yours is not on the list that does not mean we never come — there are dedicated pages for nearly all locations in Somerset, and the ones mentioned above are merely the immediate neighbours. Near the boundary, or somewhere the satnav can't find? Phone and check rather than guessing. The patch this page covers sits on our map. Kerbside, forecourt, drive, car park: the lot is territory we work on, and none of it asks your vehicle to move to us. ## Goar Knap: stuck where you pulled up The chance to pull in somewhere sensible doesn't come to everybody. A normal call for us rather than a rare one: noticed after setting off, finished up by the verge beside St Michael's Road or in a lay-by with your hazards going. Okay there? Sit with it. Not fine? Get out and away from it. It will often oblige. A diesel running on petrol limps along very willingly, and that's the trouble: restart the vehicle to get to somewhere safer and that mixture goes further into the fuel system with every mile travelled. However awkward the spot, it's no trouble for us to come to it, and that is much better for the car than driving on. ## A few miles on petrol in a diesel: what next? Here is where your M5 comes in, under 25 miles from Goar Knap. It will frequently get you onto it, and some way along, before you spot a thing. Then it's some smoke, a rough idle and power draining away — not a neat stop. Wrongly fuelled diesels rarely give you one of those. Don't start it to move it. Pull off at the next sensible junction and turn off. Presume the worst of that on a long run. Anything approaching the under 25 miles to the closest city, and the contamination has been through your filter, through your pump, through the injectors. Say so when you ring. What our technicians bring changes. Diesel has to be viscous enough to seal the tightly fitted components it runs through, and petrol thins it. That's the whole mechanism, and it explains the usual Wyndham Hill call: a diesel Audi A3 that went out there without a murmur and came back down on power, uneven at idle, perhaps smoking a little. A diesel injection system works hydraulically as well as chemically — it requires your fuel to hold pressure, not merely to burn — so when the fuel dilutes, pressure that should build then stay built starts leaking past tolerances instead, and the engine gets a poorer, later, less even delivery than it was engineered about. No part of that is the engine failing, which is the bit worth hearing: it is the fuel no longer behaving like diesel, and it stops when your fuel is put right. ## All about Goar Knap Goar Knap is a suburban area situated on the riverside in Somerset, with a mix of terraced housing and other residential properties. Goar Knap sits at an elevation of 54 metres, near the towns of New Town and Pen Mill, and is located approximately 18 miles from the city of Wells. Goar Knap forms part of a larger urban area that has developed along the river, with nearby areas including Crofton Park. Goar Knap is home to around 7480 residents, who enjoy a relatively quiet location with easy access to local amenities. ## Our visit in Goar Knap, step by step - Three things get asked before any price — the fuel that got in, the amount, and whether anything has been run since. Each answer alters the work. - We drain the tank of all the polluted mixture. - We rinse the fuel lines and clean the fuel filter, and so what's remaining in your system isn't what caused the problem. - The fuel system gets bled, on clean diesel. - Your engine is turned on and checked to confirm it runs properly on new diesel. That has it ready to drive away. We do all of this wherever the vehicle has stopped, which means it never needs to be taken to a workshop, and if it has been noticed quickly, it's very unusual for there to be long-term damage. Off the forecourt, receipt read, a couple of hundred yards, left near St Michael & All Angels. For a diesel Ford Kuga whose engine has turned, that's about the best version there is. Call us, and let the car stand with the ignition alone. Short assists, really — but a start is a start and a drive is a drive, and the filter has had weakened fuel through it, and so has your pump. Which is why the lines get purged and not just that tank drained. ## AdBlue in a diesel tank in Goar Knap is a different job AdBlue rather than petrol? Then the opening instruction is unchanged — your motor stays off — while the problem underneath it's a distinct one altogether. Petrol thins your diesel and strips the lubrication the system depends on. AdBlue? Urea dissolved in water. Put that in with the diesel and you get corrosion instead, plus residue. Usually the more significant of the two, AdBlue — and the detail lives on its own Goar Knap page. Both are ours to deal with. ## Goar Knap pricing for a petrol-in-diesel drain What changes the price is set out below, since the job is not one job and we can't honestly put a single number on this page. - This is the main one: whether your engine has been started, or driven. - How much of the wrong fuel got in, against how much that tank takes. - Whether it was petrol or AdBlue. - Whether our van can sensibly get to your car and work on it, which rests on where your vehicle is. Tell us the car, the amount and whether it has run, and you'll get a straight answer instead of a range. Not time-critical, with the vehicle at home and going nowhere? Then is fine. By now that tank is the least of that. Run a diesel and that mix goes into the filter, into your lines, into your pump, into the rail — and none of that leaves with your tank contents. A diesel Volvo XC60 that made it close to Cineworld wants its system flushed. Draining is not the same thing. ## Petrol in diesel: everyday queries around Goar Knap ## I'm on a forecourt around Goar Knap. Can you drain the vehicle here? Yes, and it is where a fair part of this work takes place. Permission from the site is the condition. Given that, a forecourt like Texaco is somewhere we're often enough, along with the rest of them locally — so name yours on the call and you'll hear if working there is possible. ## Is there a safe amount of petrol in a diesel? Proportion decides it rather than litres — and more than either, whether your engine has run. Five litres in a nearly empty tank is a separate situation from five in a full one — but either way, the thing that decides how much work is needed is if that mixture has been sucked through the fuel system. ## Already driven it with petrol in your diesel? What now? Somewhere sensible, then stop, then turn off and keep it off. Not restarting it is the single most valuable thing available to you now. Driving does shift the trouble out of that tank and into your pump and injectors, yes, and it stays fixable far more often than motorists expect. ## My warranty — does a fuel drain void it? A manufacturer's warranty outlasts a drain and flush done to a proper standard, which is no change at all. Another reason to leave it switched off: running a diesel on petrol is the thing more likely to cause a disagreement with one. ## Adding two-stroke oil, then driving home Two-stroke oil solves a distinct problem, and an old one at that. Nothing it does puts back what petrol diluted. No. Your pump still has to cope with it, as that tank still has petrol in it later. ## Do I need a main dealer for petrol in a diesel? Wherever the vehicle is, our engineers drain and clean it there, so a trip to the main dealer doesn't come into it. ## Still with the car? The engine stays off. Already driven it? Then stop somewhere safe, turn off, and let the vehicle stay that way. Cold and still, a vehicle is in the best position available — and drivers fear this much more than the recovery rate warrants. Throughout Somerset and in Goar Knap: on-site fuel draining, at home or on the forecourt or at the roadside.