Newton Poppleford: Petrol in a Diesel Car? How Worried to Be
Less than you likely are, if it has not been started. Until your ignition primes your pump, your starter turns, or the car is driven, petrol in a diesel tank just rests there and does nothing. Which makes the honest reply to the first Newton Poppleford query — "have I wrecked it?" — usually no. Keep it that way: leave your engine off then ring Petrol in Diesel. Keep reading for three things: the effect petrol has inside a diesel motor, the signs of how far it has spread, and the way to make sure you don't do it again.
Inside your engine: what petrol in a diesel does
On its way through a motor, diesel has two tasks. It burns, and before it burns it protects. Your high-pressure pump and the injectors are designed to very fine gaps, and your diesel passing through them is what keeps those surfaces from wearing against one another.
Of these two tasks, petrol handles the first badly and the second never. Being less viscous than diesel, petrol strips away the protection a fuel system needs, so a pump on the blend to wear itself. It is also made to resist igniting under compression — the reverse of what a diesel needs — which is where you hear the clattering.
Combined, those leave the shape of the trouble clear. Contact doesn't do the harm — circulation does. Where the petrol is only inside that tank, it's an issue of fuel, nothing more. After the pump has been labouring on that petrol, a mechanical issue has started: whatever is shed by a pump that is wearing travels onward to the injectors with the fuel.
How bad is petrol in a diesel? Four situations we see in Newton Poppleford
Filled up, and never started: no case is better. At a forecourt, and genuinely only there, the petrol is still confined to your tank — because everywhere else the vehicle was driven to get to it. The job is draining and cleaning on the spot.
Started for a second, or only the ignition on. Once primed, the system has drawn petrol from your tank up to the filter and your lines. Normally little more than emptying, rinsing and seeing to your filter, and so still straightforward.
Those few miles on the road meant your pump labouring on fuel thinned by petrol throughout. Tank, lines, filter, then clean fuel run through the entire circuit: that is this work, and the way the car was driven matters as much as the miles. Short trips, like the school run to Newton Poppleford Primary School, are one matter. Getting as far as Exeter, under 15 miles away, makes a very different task — as does any mileage on the M5, under 10 miles from Newton Poppleford, with the engine running hard all the way.
It protested, and only then stopped: smoke, knocking, a throttle gone soft, an idle gone lumpy. That is your engine telling you its fuel has stopped behaving like diesel. Pull up where you are — on the verge on School Lane, at the kerb, down a side road — and don't move it again. Long-term damage is very rare when a vehicle is stopped quickly, and the fuel drain and flush that still go first deal with it.
What Newton Poppleford motorists get told about petrol in a diesel — and the stories 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're left with a bigger tank, still the same mixture. The assumption behind the guidance — that diesel fuel systems tolerate petrol by percentage — is wrong.
Myth: a newer diesel copes with a bit of petrol. If anything, the reverse. At higher pressure, through finer components: that's how a newer diesel moves its fuel, and so the protection counts for more, not less.
This is the one that catches drivers. Myth: "If it starts and drives, there's no damage done." A petrol engine fed diesel normally will not run, and so the motorist stops and the harm stops with them. Feed petrol to a diesel and it generally fires up, idles and pulls away like nothing happened — all while its pump wears. Being able to run is not the same as being fine.
An outdated fix for a different issue lies behind this one. Myth: "Add some two-stroke oil and drive the vehicle home." It does not put back what petrol has diluted, and that petrol is still inside that tank later on.
If the engine has been run, part of the petrol sits in the filter and the lines, not the tank — and your next start sends it right back through your pump. So the myth "drain the tank yourself and you're sorted" does not stand up. It's also really risky to drain petrol into a can at the roadside.
Why petrol in a diesel occurs at all
Nobody does it on purpose, and it is seldom carelessness. The petrol nozzle is the slimmer of the two and slides into a diesel filler with almost no resistance; a diesel nozzle generally will not go into a petrol car at all. The forecourt makes it simple, and the mistake runs one way.
When habit and the car stop matching, it occurs. Hire cars, courtesy cars, and cars that are new to you. Two vehicles on one drive, one petrol, one diesel. A well-known forecourt with the pumps in a different order. A hurried fill on the way to Whimple with a train to catch. A new-to-you diesel Volkswagen Golf, its first fuelling, and a motorist used to petrol: exactly when it occurs. Throw in a back seat full of children, a phone call or rain, and the hand takes over.
Newton Poppleford motorists: how to prevent petrol in a diesel next time
- Not every forecourt in the UK follows green for unleaded and black for diesel, even if most usually do. Check the petrol pump's label; the colour is only a hint.
- The first fill in a strange vehicle is the time to check your filler flap — inside it, or on the cap, many motors state which fuel to use.
- A coloured fob or a sticker on the diesel's key does more than any amount of meaning to remember, in a home with one of each.
- Before the nozzle leaves the petrol pump the first time you fuel a hired or new motor, say "diesel" out loud. Silly, yes, yet it does the trick.
- Put the phone away. This is an easy mistake to make while you are thinking about something else.
- Add-on devices are available for vehicles without one, and some diesels are built with a filler that will not take a petrol nozzle. Helpful — but a backstop at best, never a reason to stop checking the label.
- Stop the moment you realise. Less petrol inside that tank makes a weaker mixture. It doesn't change what to do next, which is still not to start it.
Put petrol in a diesel in Newton Poppleford already?
The order of things is short, then. Don't switch your ignition on, and do not fire it up. The staff at the forecourt — whether at the nearest petrol station itself or wherever you filled up — will usually help roll it clear of the petrol pump if you ask. Then phone 0333 366 0103 and tell us what was put in, about how much, and if it's run.
Corrosion and deposits form the trouble with AdBlue, whereas petrol brings lost protection. So if it was AdBlue, say so — and read its own Newton Poppleford page.
What makes one Newton Poppleford petrol in a diesel task cost more than the next
Four different tasks lie behind the four scenarios above — which is why there is no fair single quote. Chiefly, your cost moves with which situation you are in. The ratio counts next, meaning how much of that tank is petrol, followed by the position of your car and whether getting to it is safe for a van.
That's why our engineers ask three queries before pricing rather than after: what got in, how much, and if it's run. A range turns into a straight figure when those replies are in.
About Newton Poppleford itself
Newton Poppleford is a village in Devon, situated near the coast and approximately 10 miles southeast of Exeter. Newton Poppleford has a population of around 1233 people and is characterized by its predominantly detached housing stock. Newton Poppleford sits at an elevation of 32 metres, close to the nearby villages of Harpford and Burrow.
Newton Poppleford and Devon: where our fuel drain cover runs
Harpford, Northmostown and Burrow are among the places near Newton Poppleford that the same vans work, answering petrol in diesel call-outs across Newton Poppleford's EX postcode area. The vehicle doesn't need to come to us: our technicians drain at a forecourt, in a supermarket car park, in a lay-by or on your own drive.
Newton Poppleford: still at the pump?
Then, you could not be in a better spot. Keep it off. Ring.