--- title: Drain Petrol From a Diesel Car — Upton Cross canonical: https://www.petrolinadieselcar.co.uk/petrol-in-diesel/upton-cross-cornwall/ location: Upton Cross county: Cornwall latitude: 50.524090 longitude: -4.421580 service: Petrol in a Diesel Car updated: 2026-10-23 --- # Upton Cross: Put Petrol in a Diesel Car? With the tank still carrying the petrol and the motor not yet turned over, nearly every job requires only a drain, so keep your engine off. That result is decided in the minutes immediately after filling up, rather than by the amount that got in. Across Upton Cross and the remainder of Cornwall, Petrol in Diesel drains your car and flushes it where it stands, whether by a roadside, on a drive or at a forecourt. Phone and then we can explain what comes after that before you attempt anything else. ## What to do first about petrol in a diesel - Do not crank it. Turned on regardless? Then never depend on it. Diesel in a petrol car generally cannot run, and so the driver stops and the damage stops with them. Petrol in a diesel? It starts. It idles. It moves off normally, for a few miles. Most people get that confused. It isn't fine — the fuel system is grinding every mile you do. - Two things, diesel: it combusts, and on the way through it keeps your injection pump and injectors lubricated. Petrol only manages the one. Which is why the ignition is left off as well — flick it on and you commonly prime that system, and that's petrol leaving the tank for exactly those components. - Topping up clears nothing. It leaves you a fuller tank of the same mix, because a diesel fuel system doesn't accept petrol by percentage the way that advice implies — so never put diesel on top to water down it. Type is irrelevant too: super unleaded is petrol. - Remain where you are if you sensibly can. A vehicle that has not shifted is the easiest one to deal with, and our team would rather get to a difficult location than have it started. If you're stopped on the verge on B3254, switch your hazards on and keep the vehicle there. - Check where you are before phoning. A postcode beginning PL14 5, and the name of whatever is closest to you. Otherwise our van circles rather than showing up. - Three facts decide your whole call-out: the stuff you tipped in, the rough volume involved, and whether anything has been running since. The number is 0333 366 0103. The drive in is what pushed weakened diesel through the pump. Standing still has drawn nothing. Petrol in a diesel Volkswagen Golf, parked outside Liskeard all day, waits harmless in your tank whilst it waits. Call us first — before the keys go in. ## Can petrol be pumped from a diesel at a forecourt? Most of the job starts at the pump, so a good part of it gets done there. Our technicians work on garage forecourts all the time, with the site's agreement, so if you are still at BP that's typically where the drain gets done. A filling station is the only location this can be spotted before your engine has fired. We can still sort it out where it stands, even away from the pumps. In a car park, on a private drive or in a lay-by, the car has been fired up and driven there, and that drew fuel through the filter and into the high-pressure fuel pump, all the way from the tank. None of that is a calamity, though the flush then has to reach past your tank to the lines and the fuel filter, and the few seconds between checking the till receipt and going for your key are what determine that. The staff will normally offer to move the car out from the petrol pump so the next customer can get by. That's worth doing. Firing it to roll four vehicle lengths is not. ## Upton Cross and the places near it Upton Cross is a rural village, and so we go out to it and to the villages by it on the usual trips: Upton, Sutton, Netherton, Caradon Town and Downgate. If yours is not on the list it doesn't mean we don't come — there are separate pages for nearly all places in Cornwall, and the ones listed above are merely the closest neighbours. Phone to ask rather than guessing, particularly where you are on a boundary or somewhere the satnav gets wrong. That map is the patch this page covers. We work by the road, at forecourts, on driveways and at car parks over all of that, and your car doesn't need to come to us. ## Upton Cross: broken down wherever you pulled up The opportunity to pull over somewhere suitable doesn't come to everybody. Set off, then twigged? Ended up along the verge beside Carnedon, or stuck in some lay-by with the hazards flashing? That is a normal call here. Not an unusual one. Wait by your car when it's sensible to be in it, and out of the car when it's not. Don't fire it up to reach a safer place. It'll go — a diesel on petrol normally obliges — and each mile of obliging pulls the mix deeper into your fuel system. Pressing on does the car far more harm than a van heading out to an inconvenient spot, and that's no trouble for us. Do not chance it. The journey home from Caradon Inn is entirely possible, which is exactly the problem — a weakened tank does not stop a diesel starting or pulling away, it just wears the components the fuel is supposed to lubricate. Phone us, and let the BMW 1 Series stay where it sits. ## So you've run it? Petrol in a diesel after some miles This is where the M5 comes into it — under 50 miles from Upton Cross. It will frequently get you onto it, and some way along, before you spot a thing. Then it's smoke, an uneven idle and power falling away — not a neat stop. Misfilled diesels seldom give you one of those. Take the first junction that is safe, pull up there, and don't restart it to reposition. It changes what we bring, so tell us when you call: on a longer trip — anything near the under 25 miles to the closest city — take it the contamination has been through the fuel filter, your pump and your injectors. ## A bit about Upton Cross Upton Cross is a small village in Cornwall, situated inland at an elevation of 161 metres. Upton Cross lies near several other settlements, including Upton, Sutton, and Netherton, and is approximately 16 miles from Plymouth. Upton Cross has a population of around 696 people, predominantly living in detached houses. Upton Cross is located in the South West region of England, about 199 miles west of London. ## When our technicians arrive with you around Upton Cross: what happens - Our technicians ask first, price after. What got in? How much? Has the engine run? Those responses change what the work really is. - The contaminated fuel is pulled from the tank. - What is left in your system shouldn't be what started the issue, and so your fuel lines get flushed and the fuel filter cleaned. - Fresh diesel goes in, and then the system gets bled. - Our engineers fire it up and make sure it runs correctly on clean diesel. From there, you are ready to drive away. We do all of this wherever the car has stopped, which means it never needs to be taken to a garage, and if it has been caught quickly, it is very uncommon for there to be long-term damage. Why we're direct about not driving on: your pump rests ahead of the fuel injectors, so whatever a wearing pump loses moves downstream with the fuel. Leave the Vauxhall Insignia close to Linkinhorn Parish Hall then ring us. ## A different job: AdBlue in a diesel tank around Upton Cross If what went in was AdBlue rather than petrol, the opening instruction is the same — do not start it — yet the issue isn't. Petrol dilutes the diesel and takes away the lubrication your fuel system depends on. Corrosion and build-up are what a diesel tank gets instead, since AdBlue is urea dissolved in water. Both are ours. There is a separate Upton Cross page for AdBlue removal, with the detail on it — including the reasons it often turns out to be the worse of the two. Hire car or company car? Ring them before you ring us — some contracts want the hire firm to authorise the work, and sorting that out first is a great deal faster than sorting it later on. Then call us about the Volvo XC60 close to Saint Paul's Church, and don't worry that you cannot say how full the tank was. Almost nobody can, in a motor they collected two days ago, and our engineers work it out there. The reason our technicians ask is that petrol in a diesel does its damage as a ratio: the same few litres in an almost empty tank is a far stronger mixture than in a full one. Petrol is rated on how well it resists igniting under pressure, which is the opposite of what a diesel needs — so the stronger that mix, the more it rattles, smokes and goes flat. ## Paying for a petrol-in-diesel fuel drain in Upton Cross One figure wouldn't be honest here, because this is not one job. These are the things that change it: - Whether the motor has been run or driven. This is the key one. - How much of the wrong fuel went in, measured against how much the tank can hold. - Whether it is unleaded or AdBlue. - Where is it? And can a technician reach it and work there safely? Tell us your car, the amount and whether it has run, and you'll get a firm answer instead of a range. If it's not time-critical — the car is at home and going nowhere — works too. Cleared, not drained — that's what a diesel Citroen C4 which got as far as Sterts Theatre needs. Running a diesel puts that blend into the filter, the lines, the pump and the rail, none of which empties with that tank, so by now your tank holds the smaller part of the trouble. ## Upton Cross drivers ask us these about petrol in diesel ## Can you do a fuel drain at a petrol station in Upton Cross? Plenty of what our technicians do happens nowhere else. So yes. Tell us which one you're at when you ring and we'll tell you whether we can work there. With the station's agreement we work at another forecourt nearby and the other forecourts nearby regularly. ## How much petrol is too much for a diesel? It hinges on the ratio rather than the litres, and a lot more on whether the motor has run. An almost empty tank with five litres in it, against a full one with the same five: distinct scenarios, of course. Either way, the work needed comes down to one thing, which is whether the fuel system has had that blend pulled through it. ## I drove it after putting petrol in my diesel. Now what? Turn off somewhere sensible, and keep it that way after you stop. Not restarting it is the single most valuable thing available to you now. Driving does shift the problem out of that tank then into the pump and injectors, yes, and it remains recoverable far more regularly than people fear. ## My warranty — does a fuel drain void it? A manufacturer's warranty survives a drain and flush done to a good standard, which is no alteration at all. Another good reason to leave it switched off: running a diesel on petrol is the thing more likely to cause a dispute with one. ## Could I put some two-stroke in and just drive? No. It belongs to a separate issue from a separate era, and petrol has thinned something no oil of that kind restores. Later? Still petrol in the tank, and a pump that has to cope with the stuff. ## Main dealers and petrol in a diesel There is no need to bring it to a main dealer, as our technicians drain and flush your car wherever it is. ## Is the car still with you? Never turn the car on again. Driven it already? Then somewhere safe, stop, turn off, and no restarting it later on. This is recoverable from much more often than people fear, and a still, cold vehicle is the best place to be in. Emptying misfilled vehicles, Upton Cross and the rest of Cornwall, wherever they are. Kerbside. Forecourt. Home.