How Worried Should You Be? Petrol in a Diesel Car in Coxhoe
Likely less than you already are — as long as nobody has started the car. "Have I ruined it?" is the first thing everyone in Coxhoe asks, and the honest answer is usually no, since petrol left in a diesel tank hurts nothing till it's dragged through the system — by ignition priming, by your starter, or by being driven. To keep the vehicle that way, call Petrol in Diesel then leave your motor switched off. Read on for three things: the effect petrol has inside a diesel engine, the clues of how far it has spread, and the way to make sure you don't do it again.
Petrol in a diesel: what does it do to the motor?
Two jobs fall to diesel on its journey through a motor. It protects to begin with, and only then does it burn. Made to very fine clearances, the fuel injectors and the pump rely on the diesel moving through them to stop their surfaces wearing against one another.
Petrol handles the first job badly and the second not at all. A pump working on a petrol mixture is wearing itself out, since petrol is thinner than diesel and takes away the protection the fuel system depends on. Petrol is also designed to resist igniting under compression — the reverse of what a diesel wants from its fuel — and that is where any knocking starts.
Combined, those make the shape of the issue clear. The damage is done by circulation, not by contact. All a tank with petrol in it amounts to is a fuel issue. After the pump has been labouring on that petrol, a mechanical problem has begun: anything shed by a pump that is wearing travels onward to the injectors with the fuel.
Four scenarios our engineers see around Coxhoe: how bad is petrol in a diesel?
Filled but never started — as good as it gets. Just that tank has petrol in it, and so the task is clearing that tank and rinsing the fuel system where the car stands. This scenario can only really take place at a forecourt: anywhere else, your car got there by being driven.
A brief spell of running, or just the ignition on. Petrol has left that tank and got to the filter and the lines, since the fuel system has been primed. Drain, flush, see to the fuel filter: still usually simple.
Driven a couple of miles. Now the pump has spent those miles labouring on diluted fuel. The work is your tank, your lines, the fuel filter and fresh fuel through the entire circuit, and how hard the car was driven counts as much as how far. Driving the children to Coxhoe Primary School is one sort of trip. Very different a second time: a trip to Durham, under 10 miles away, or any miles on the A1(M), under a mile from Coxhoe, where your engine kept working hard.
It complained, and only then stopped: smoke, knocking, a throttle gone soft, an idle gone lumpy. What you are hearing is the motor signalling fuel that no longer behaves like diesel. Leave it wherever it has stopped: a lay-by, a quiet street, the verge on Cornforth Lane. Permanent damage is very rare when a vehicle is pulled over early, and the drain and flush-through that still go first sort it out.
Myths Coxhoe drivers hear about petrol in a diesel
"Top it up the rest of the way with diesel and it will be fine" — a myth. It won't. Topping up takes out nothing; it gives you a fuller tank of the same mixture. Percentage is not how a diesel fuel system copes with petrol, however much that advice supposes.
Myth: "A current diesel can cope with a bit of petrol." If anything, the reverse. Lubrication matters more on current diesels, not less, since their fuel runs through smaller parts at higher pressure.
Myth: "If it starts and drives, there's no damage done." This is the one that fools drivers. The driver of a petrol engine fed diesel usually has no choice but to stop, since it will not run, and the harm stops there. A diesel fed petrol normally starts, ticks over and drives away as though nothing has happened, whilst your pump wears. Being able to run is not proof of being fine.
Myth: "Add some two-stroke oil and drive it home." It is an old workaround for a different issue. What petrol has thinned stays weakened, and the petrol stays inside your tank regardless.
Myth: "Drain that tank yourself and you are sorted." After the engine has been run, some of that petrol is no longer in your tank: it is in the fuel filter and the lines, and it goes right back through the pump at your next start. And, a can of petrol filled by the roadside is genuinely risky.
How does petrol in a diesel take place?
On purpose? Never. Through carelessness? Rarely, if ever. The petrol nozzle is the narrower of the two and slides into a diesel filler with almost no resistance; a diesel nozzle mostly won't go into a petrol vehicle at all. The forecourt makes it simple, and the slip runs one way.
When habit and the car stop matching, it happens. Hire cars, courtesy cars, and cars that are new to you. Two motors on one driveway, one petrol, one diesel. The pumps in a different order on a familiar forecourt. A rushed fill en route to Durham with a train to catch. Precisely the moment it takes place: after years of driving petrol, someone fills a diesel Volkswagen Golf for the first time. Your 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 Coxhoe: avoiding petrol in a diesel
- The label is what matters, and so check the petrol pump instead of the colour: in the UK unleaded handles are normally green and diesel black, but not on every forecourt.
- The first fill in a strange vehicle is the time to check your filler flap — inside it, or on the cap, plenty of vehicles state the fuel to use.
- Label the key. In a household with one of each, a coloured fob or a sticker on the diesel's key does more than any amount of meaning to remember.
- Before the nozzle leaves the pump the first time you fill a hired or new motor, say "diesel" out loud. Daft, yes, yet it works.
- Put your phone away. This is an easy mistake to make while you're thinking about something else.
- A misfuel inhibitor helps, up to a point. Some diesels have a filler designed to reject a petrol nozzle, and add-on devices are available for cars without one. They are a backstop, not a reason to stop reading the petrol pump.
- Less petrol means a thinner mixture, and so stop as soon as you realise — while remembering that your next stage is unchanged. It's still not to crank it.
Coxhoe: already put petrol in a diesel?
In that case, there's only a short order of things. Do not crank it, and don't turn your ignition on. Ask the staff to help you roll it away from the petrol pump if you're still at the forecourt, whether that's Shell or somewhere else. Phone 0333 366 0103 next, with three facts — the fuel, the approximate quantity, and whether it's run.
Corrosion and deposits are the problem with AdBlue, where petrol brings lost lubrication. So if it was AdBlue, say so — and see its own Coxhoe page.
Coxhoe petrol in a diesel tasks: why one costs more than another
There is no honest single quote for this, since the four scenarios above are four separate tasks. Which of them you are in is chiefly what shifts your cost. Where the car is counts too, and whether our van can safely get to it, after the proportion of petrol to what that tank holds.
What got in, how much, and if it's run — three queries we ask before quoting, not after, for precisely that reason. Given those replies, you get a straight figure rather than a range.
About Coxhoe
Coxhoe is a village situated on the banks of a river in County Durham, with an elevation of around 111 metres. Coxhoe lies approximately 5 miles from the city of Durham and is surrounded by nearby villages such as Garmondsway and Kelloe. Coxhoe has a population of around 2205 people and predominantly consists of semi-detached housing. Coxhoe is located in the North East region of England, about 228 miles north of London.
Fuel drain cover around Coxhoe and across Durham
Garmondsway, Kelloe and Tursdale are among the locations around Coxhoe that the same vans work, answering petrol in diesel calls across Coxhoe's DH postcode area. A forecourt, a supermarket car park, a lay-by or your own driveway are all locations we drain, and the vehicle does not need to move to us.
Still at the pump in Coxhoe?
In that case, you could not be in a better spot. Ring, and keep it switched off.