Should You Worry? Petrol in a Diesel Car in Eveninghill
Probably less than you are now — provided nobody has started it. Everyone around Eveninghill begins with "have I ruined it?", and the honest answer is generally no: petrol left inside the tank of a diesel stays harmless until priming, cranking or driving pulls it into the fuel system. To leave the car that way, call Petrol in Diesel and leave the motor alone. What petrol actually does to a diesel, how to judge how far it has gone, and how to stop it from happening again: that is the remainder of this page.
Inside the motor: what petrol in a diesel does
Diesel does two jobs on its way through an engine. Before it ignites, it lubricates — and then it burns. Designed to extremely fine gaps, the fuel injectors and the pump depend on your diesel moving through them to keep their surfaces from wearing against one another.
The second task petrol doesn't do at all, and the first it does badly. It is runnier than diesel and takes away the lubrication the fuel system rests on, and so a pump running on a petrol mixture 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.
Taken together, they show what shape the problem takes. The damage is done by circulation, not by contact. A tank with petrol in it is a fuel issue. Whatever a worn pump sheds goes on, carried by the fuel, into the fuel injectors downstream, which is why a pump that has worked on the petrol is where a mechanical issue begins.
How serious is petrol in a diesel? Four situations we see around Eveninghill
Filled up, and not started: nothing beats it. That petrol is inside the tank and just that tank, and the job is a drain and a flush where your car sits. This is the one scenario that can only truly happen at a forecourt, as anywhere else your car has been driven to get there.
A brief spell of running, or merely the ignition on. With your system primed, the lines and filter already contain petrol that came from that tank. Normally little more than clearing, rinsing and sorting your filter, so still simple.
Some miles driven, and your pump has spent every one of them running on weakened fuel. Miles is only half of it; how hard it was driven counts just as much. Either way the work runs to that tank, the fuel lines, the filter and fresh fuel through the entire system. On the school run to Thursby Primary School, the distance is short. Any distance on the M6, under 10 miles from Eveninghill, means the engine working hard throughout, and a run to Carlisle, under 10 miles away, is a very different job too.
Driven till it protested. Clattering, a ragged idle, smoke, a throttle that has gone soft. That's your motor telling you its fuel no longer is acting like diesel. Whether it's the verge on Curthwaite Road, a lay-by or a side road, stop where you are and leave it. The fuel drain and flush still come first, and they take care of it: when a vehicle is pulled over soon, long-term damage is very rare.
Myths Eveninghill drivers hear about petrol in a diesel
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 — your tank just holds more of the same mixture. A diesel fuel system does not accept petrol by percentage in the way that advice supposes.
"Newer diesels can handle a little petrol" — a myth, and closer to the opposite. A modern diesel runs its fuel through more precise components at higher pressure, which makes the protection matter more, not less.
"It starts, it drives, so there is no harm" — the myth that trips up most drivers than any other. A petrol motor fed diesel normally will not run, so the driver stops and the damage stops with them. Feed petrol to a diesel and it usually starts, ticks over and pulls away like nothing has happened — all while its pump wears. Fine and running are not the same at all.
An outdated workaround for a different issue is behind this one. Myth: "Add some two-stroke oil and drive it home." What petrol has diluted remains diluted, and that petrol stays inside your tank anyway.
Myth: "Drain that tank yourself and you are sorted." After your engine has been run, some of that petrol is no longer inside that tank: it's in the fuel filter and your lines, and it goes straight back through your pump on the next start. And, a can of petrol drained by the kerbside is genuinely hazardous.
Petrol in a diesel: how does it happen?
It's rarely carelessness, and nobody does it on purpose. A diesel nozzle generally won't go into a petrol car, but the smaller petrol nozzle goes into the filler of a diesel nearly without resistance — so forecourts make this one mistake easy, and just in that direction.
When routine and the car stop matching, it occurs. Courtesy car, hire car, or a motor that is brand new. Two motors on one driveway, one petrol, one diesel. Your usual forecourt, its pumps now in a different order. Racing for a train at Dalston (Cumbria) and fuelling up en route. A new-to-you diesel Volkswagen Golf, its first fuelling, and a motorist used to petrol: exactly when it happens. Add a back seat full of children, a phone call or rain, and the hand takes over.
How to avoid petrol in a diesel at your next fill-up around Eveninghill
- Not every forecourt in the UK follows green for unleaded and black for diesel, though most usually do. Read the pump's label; the colour is just a hint.
- In a car you do not know, look inside the flap over your filler or at the cap before your first fill: plenty of motors print the fuel there.
- Mark your 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 intending to remember.
- Say it before you lift it. On your first fill in a new or hired car, say "diesel" aloud before you take the nozzle off the pump. It seems silly and it works.
- Whilst you're thinking about something else, this is an easy mistake to make — so tuck the phone away.
- Add-on devices exist for vehicles without one, and some diesels are built with a filler that will not take a petrol nozzle. Helpful — but a backstop only, never a reason to stop checking the label.
- Stop the moment you notice. Less petrol in that tank makes a thinner mixture. It does not change what to do next, which is still not to fire it up.
Put petrol in a diesel in Eveninghill already?
Short and simple, then, is the order of things. Leave it unstarted, with your ignition off too. Yet at the forecourt, at Esso or anywhere else? Ask the attendants to help you roll the vehicle clear of the pump. Then call 0333 366 0103 and tell us what was put in, about how much, and whether it has run.
If it was AdBlue rather than petrol, say so. That is a separate problem — corrosion and deposits and not lost protection — and it has its own page for Eveninghill.
Why one petrol in a diesel job in Eveninghill costs more than another
Four different jobs lie behind the four scenarios above — which is why there is no honest single price. What moves the cost is chiefly which of them you're in. After that it is the ratio — how much petrol went in against how much your tank takes — and then where your car is and whether a van can get to it safely.
What was put in, how much, and whether it has run — three questions we ask before quoting, not after, for precisely that reason. Given the replies, there is a straight figure instead of a range.
About Eveninghill itself
Eveninghill is a suburban area situated on the riverside in Cumbria, with a relatively low elevation of 42 metres. Eveninghill lies close to the city of Carlisle, approximately 6 miles away, and is near other local places such as Thursby and West Curthwaite. Eveninghill has a population of around 983 people and predominantly features detached housing. Eveninghill is located in the North West region of England, about 260 miles from London.
Fuel drain cover across Cumbria, Eveninghill included
Petrol in diesel jobs in Eveninghill — part of the CA postcode area — go to teams that likewise cover the places about it, Thursby, West Curthwaite and Moorend among them. Our technicians drain where your vehicle is — your own drive, a lay-by, a supermarket car park, a forecourt — so it never needs to come to us.
Still at the pump in Eveninghill?
Then, you couldn't be in a better spot. Phone, and keep it switched off.