Should You Worry? Petrol in a Diesel Car in Great Chart
Less than you probably are, if it has not been started. Everyone in Great Chart begins with "have I wrecked it?", and the fair answer is usually no: petrol left inside the tank of any diesel stays harmless till priming, cranking or driving pulls it into the fuel system. Petrol in Diesel is who to ring, with the engine left off, so it stays that way. Keep reading for three things: the effect petrol has inside a diesel engine, the signs of how far it has got, and the way to make sure you never repeat it.
The engine and petrol in a diesel: what goes on
Passing through an engine, diesel is doing two things at once. Oiling comes before burning; it does both. Very fine gaps are built into the fuel injectors and the high-pressure fuel pump, and only the diesel flowing through stops those surfaces grinding together.
Badly at the first, not at all at the second: that is petrol. It is runnier than diesel and strips away the protection your fuel system hinges on, so a pump running on a petrol blend is a pump wearing itself. And petrol is made to resist igniting under compression, which is the reverse of what a diesel needs from its fuel. That is where the knocking comes from.
Seen together, they make clear what shape the trouble takes. It's circulation that does the damage, not contact. Where the petrol is only in the tank, it is an issue of fuel, nothing more. A pump that has been labouring on that petrol is the start of a mechanical one, and whatever a worn pump sheds moves on with your fuel to your injectors further on.
Four situations our engineers see around Great Chart: how bad is petrol in a diesel?
Filled but never started — as good as it gets. Only that tank has petrol in it, and so the task is clearing your tank and cleaning the system where your car sits. This scenario can only really take place on a forecourt: anywhere else, the car got there by being driven.
Your ignition switched on, or a short start. Your system has been bled, and so petrol has left the tank and got to your filter and the lines. Still generally straightforward: drain, flush, and the filter dealt with.
Driven a couple of miles. Now the pump has spent these miles working on weakened fuel. How hard your car was driven matters as much as how far, and the work covers the tank, the lines, the fuel filter and fresh fuel through the whole circuit. A school run to Great Chart Primary School is one matter. Very different once more: a run to Canterbury, under 15 miles away, or any distance on the M20, under 3 miles from Great Chart, where the motor never stopped working hard.
Driven on till it complained — rattling, smoke, a lumpy idle, a soft throttle. The motor is telling you your fuel is no longer acting like diesel. Whether it is the verge on The Street, a lay-by or a side road, stop there then leave it. Lasting damage is very uncommon when a car is pulled over early, and the drain and flush-through that still come first take care of it.
Great Chart motorists and the petrol in a diesel stories they hear
"Top it up the rest of the way with diesel and it'll be fine" — a myth. It won't. Topping up removes nothing; it gives you a bigger tank of the same mix. A diesel fuel system does not accept petrol by percentage in the way that advice assumes.
If anything, the opposite is true. Myth: "A modern diesel can cope with a bit of petrol." At higher pressure, through more precise parts: that's how a current diesel moves its fuel, and so the protection matters for more, not less.
This is the one that catches people. Myth: "If it starts and drives, there's no damage done." Diesel in a petrol motor usually leaves a motor that won't run: the driver stops, and so does the harm. Feed petrol to a diesel and it normally starts, ticks over and drives away as if nothing has happened — all the while its pump is wearing. Fine and running aren't the same at all.
"A drop of two-stroke oil and drive it home" — a myth, borrowed from a fix from years ago, for a distinct problem. What petrol has diluted remains diluted, and that petrol remains inside the tank regardless.
"Drain it yourself and you're sorted" — a myth, since after it's been running some petrol sits in your filter and lines, waiting to go right back through the pump at the next start. On top of that, petrol cleared into a can by the road is truly risky.
How does petrol in a diesel take place?
Carelessness is seldom the cause, and no one means to do it. The forecourt makes it easy: the petrol nozzle is the smaller of the two, and it slides into a diesel filler with almost no resistance, whilst a diesel nozzle generally won't go into a petrol car at all. So the mistake runs one way.
Habit and the car falling out of step is how it occurs. Hire cars, courtesy cars, and motors that are new to you. Households running one of each, petrol and diesel. A forecourt you know, only with its pumps arranged differently. Racing for a train outside Ashford International and filling up en route. Exactly the moment it takes place: after years of driving petrol, someone fills a diesel Renault Clio for the first time. With rain, a call coming in, or a car full of children to deal with, your hand simply does what it has always done.
How to avoid petrol in a diesel on your next fill-up around Great Chart
- The label is what matters, so read the petrol pump instead of the colour: in the UK unleaded handles are usually green and diesel black, but not on every forecourt.
- Many vehicles state the fuel inside the filler flap or on the cap, so check there on your first fill in any motor you do not know.
- 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.
- "Diesel", aloud, before you lift the nozzle — every time a new or hired car needs its first tank. It sounds silly. It does the trick.
- Thinking about something else is when this becomes an easy mistake to make, and so tuck the phone away then keep your mind on the petrol pump.
- A misfuel inhibitor helps, up to a point. Some diesels have a filler designed to refuse a petrol nozzle, and add-on devices exist for vehicles without one. They are a safety net, not a reason to stop checking the pump.
- Less petrol makes a thinner mix, and so stop the moment you realise — while remembering that the next step is unchanged. It is still not to crank it.
Great Chart: already put petrol in a diesel?
Then, there is just a short order of things. Do not start the car, and do not switch your ignition on. The staff on the forecourt — whether at BP itself or wherever you filled up — will usually help roll it clear of the pump if you ask. Next, 0333 366 0103. We will ask what was put in, about how much, and if it's been run.
AdBlue, not petrol? Then tell us. Corrosion and deposits, not lost lubrication, make it a separate problem — Great Chart has a page just for it.
Great Chart petrol in a diesel jobs: why one costs more than another
The four scenarios above are four separate jobs, so no single quote for this would be honest. The situation itself does most of the work of moving your cost. The proportion counts next, meaning how much of the tank is petrol, followed by the position of the car and whether reaching it is safe for a van.
Ahead of any quote, not after, we ask three queries: the fuel that got in, the amount, and if it has run. That's why. Their answers are what change a range into one firm number.
About Great Chart and where it is
Great Chart is a village in Kent, situated on the River Great Stour, with an elevation of around 43 metres. Great Chart has a mix of housing types, but semi-detached homes are predominant, and it is located near other small communities like Singleton and Chilmington Green. Great Chart is close to the city of Canterbury, which is about 14 miles away, and is also within commuting distance of London, at approximately 48.5 miles away. Great Chart remains a small, rural village with a population of around 865 people.
Across Kent and around Great Chart: fuel drain cover
Great Chart waits in the TN postcode area, and our vans that answer petrol in diesel call-outs there work the places near it as well — Singleton, Chilmington Green and Brookfield among them. The vehicle doesn't need to come to us: our technicians drain on a forecourt, in a supermarket car park, in a lay-by or on your own drive.
At the pump around Great Chart, still?
Then, you could not be in a better place. Phone, and keep it turned off.