Brightlingsea: Petrol in a Diesel Car? How Worried to Be
Not started? Then less worried than you probably feel. Till your ignition primes your pump, your starter turns, or your vehicle is driven, petrol in a diesel tank just waits there and does nothing. Which makes the truthful reply to the first Brightlingsea question — "have I ruined it?" — usually no. To leave the vehicle like that, call Petrol in Diesel then leave the engine switched off. The remainder of this page sets out what petrol actually does to a diesel, how to tell how far it has got, and how to make sure it does not happen to you again.
What petrol in a diesel does to your engine
Passing through a motor, diesel is doing two jobs at once. It ignites, and before it burns it lubricates. Designed to extremely fine clearances, the injectors and the pump depend on your diesel moving through them to stop their surfaces wearing against one another.
Of these two tasks, petrol handles the first badly and the second never. It is runnier than diesel and takes away the lubrication your fuel system hinges on, and so a pump running on a petrol mixture is a pump wearing itself. And petrol is designed to resist igniting under compression, which is the reverse of what a diesel needs from its fuel. That is where the clattering comes from.
The shape of the issue is plain when you put those together. Contact does not do the harm — circulation does. Any tank with petrol in it is a fuel problem. Whatever a worn pump sheds goes on, borne by your fuel, into the fuel injectors downstream, which is why a pump that has been working on the petrol is where a mechanical problem starts.
Brightlingsea, petrol in a diesel: four cases, from mild to major
Fuelled up, not once started. The best case there can be. Being on a forecourt is what makes this possible: elsewhere, the car has been driven there to begin with. With the petrol kept inside your tank alone, it's drained and flushed right where it stands, and nothing more is needed.
Started for a moment, or only your ignition on. With the fuel system primed, the lines and filter already contain petrol that has come from your tank. Still normally simple: drain, flush, and the fuel filter dealt with.
Your pump now worked a few miles on weakened fuel — that's what driving it meant. Tank, lines, filter, then clean fuel put through the entire circuit: that's the work, and the way your car was driven matters as much as the mileage. On the school run to Brightlingsea Primary School and Nursery, the miles is short. Very different a second time: a trip to Colchester, under 10 miles away, or some distance on the M11, under 50 miles from Brightlingsea, where the engine never stopped working hard.
Driven until it complained. Rattling, a ragged idle, smoke, a throttle that has gone soft. The fuel is not behaving like diesel any more, and your engine is telling you. Pull up wherever you are — the verge on Lady Smith Avenue, a lay-by, a side street — then leave it where it is. A vehicle stopped quickly very seldom has lasting damage, since the drain and the flush, which still come first, take care of it.
What Brightlingsea people get told about petrol in a diesel — and the myths in it
It will not be fine. The myth: "Fill it the rest of the way with diesel and it'll be." Nothing comes out when you top up — that tank just carries more of the same blend. The idea behind the guidance — that diesel fuel systems tolerate petrol by percentage — is wrong.
"Current diesels can handle a little petrol" — a myth, and closer to the reverse. A current diesel sends its fuel through smaller components at higher pressure, which makes the protection matter more, not less.
One myth that catches motorists off guard: if it starts and drives, it must be unharmed. The driver of a petrol motor fed diesel normally has no choice but to stop, since it will not run, and the harm stops there. While your pump wears, a diesel fed petrol usually starts, idles and drives away as though nothing has happened. Running does not mean fine.
An outdated fix for a distinct problem is behind this one. Myth: "Add some two-stroke oil and drive the vehicle home." What petrol has thinned stays weakened, and that petrol remains inside that tank regardless.
The next start draws petrol back round your pump from the fuel lines and the filter, where some of it ends up after the engine has run. That's why draining your tank yourself doesn't sort it — a myth. Also, a can of petrol filled by the roadside is truly dangerous.
How petrol ends up: petrol in a diesel
No one does it on purpose, and it is seldom carelessness. A diesel nozzle mostly will not fit a petrol vehicle, but the smaller petrol nozzle goes into the filler of a diesel nearly without resistance — so forecourts make this one error simple, and only in that direction.
Routine and the car getting out of step is when it takes place. A new car, a hire car or a courtesy car. A household with one petrol and one diesel on the driveway. A familiar forecourt with the pumps in a different order. A hurried fill on the way to Alresford with a train to catch. A new-to-you diesel Peugeot 308, its first fuelling, and a motorist accustomed to petrol: precisely when it occurs. Your hand repeats what it has always done when you add rain, a phone call or a back seat full of children.
How to prevent petrol in a diesel on your next fill-up around Brightlingsea
- A green handle for unleaded and black for diesel is normal in the UK — but not on every forecourt. Trust the label on the pump, not the colour.
- In a vehicle you do not know, look inside the flap over your filler or at the cap before the first fill: many motors print the fuel type there.
- Good intentions count for less than a sticker or a fob in a bright colour on the diesel's key if a household has one of each. So label it.
- Before the nozzle comes off the pump the first time you fuel a hired or new vehicle, say "diesel" out loud. Silly, yes, but it works.
- Mistakes like this are easy to make while your mind is on something else, so your phone goes away.
- Add-on devices exist for cars without one, and some diesels come with a filler that will not accept a petrol nozzle. Useful — but a backstop at best, never a reason to stop checking the label.
- Stop the moment you realise. Less petrol in your tank means a weaker mixture. It does not change what to do next, which is still not to start the car.
Brightlingsea: already put petrol in a diesel?
Then, there's only a short order of things. Do not switch your ignition on, and do not crank it. The attendants at the forecourt — whether at Texaco itself or wherever you filled up — will normally help push it clear of the petrol pump if you ask. Next, 0333 366 0103. We'll ask what got in, roughly how much, and if it's been run.
Say so if it was AdBlue instead of petrol: it's a separate problem, with its own page for Brightlingsea, since AdBlue brings corrosion and deposits instead of lost lubrication.
Brightlingsea petrol in a diesel jobs: why one costs more than another
An honest single price doesn't exist here: four situations, four separate tasks. What moves the cost is chiefly which of them you are in. Next it's the ratio — how much petrol went in against how much the tank takes — and after that where your car is and whether a technician can get to it safely.
That's why we ask three questions before costing rather than after: what got in, how much, and if it has run. Those answers are what change a range into one firm number.
About Brightlingsea
Brightlingsea is a coastal town in Essex, situated on the Colne Estuary at an elevation of around 11 metres. Brightlingsea lies near the cities of Colchester and Clacton-on-Sea, and is close to the nearby places of Point Clear, Thorrington, and East Mersea. Brightlingsea has a population of approximately 9052 people, and its housing stock is predominantly semi-detached homes.
Fuel drain cover across Essex, Brightlingsea included
Petrol in diesel jobs in Brightlingsea — part of the CO postcode area — go to teams that also cover the spots about it, Point Clear, Thorrington and East Mersea among them. Our technicians drain wherever the car is — your own driveway, a lay-by, a supermarket car park, a forecourt — so it never needs to come to us.
Brightlingsea: still at the pump?
Then, you could not be in a better position. Keep it off. Phone.