Enfield Lock: Petrol in a Diesel Car? How Worried to Be
Provided it hasn't been started, you can worry far less than you likely are. Petrol sitting in a diesel tank does nothing to your motor till something pulls it through your fuel system — your ignition priming your pump, the starter, or driving on its own. So the fair answer to the first query anyone in Enfield Lock asks, "have I wrecked it?", is normally no. To leave it like that, call Petrol in Diesel and leave the motor alone. The remainder of this page sets out what petrol really does to a diesel, how to tell how far it has got, and how to make sure it doesn't happen to you again.
Inside your engine: what petrol in a diesel does
On its way through a motor, diesel does two tasks. It lubricates first, and after that does it burn. The high-pressure fuel pump and the fuel injectors are built to extremely fine gaps, and the diesel passing through them is what stops those surfaces from wearing against each other.
Badly at the first, not at all at the second: that's petrol. The clattering comes from petrol being made not to ignite when compressed, which is precisely the reverse of what a diesel needs. On top of that it is runnier than diesel, it strips away the protection the fuel system rests on, and any pump running on that mix is wearing itself.
Seen together, they make clear what shape the problem takes. Not contact but circulation is what does the damage. Any tank with petrol in it is a fuel issue. After your pump has been running on that petrol, a mechanical issue has begun: whatever is shed by a pump that is wearing travels downstream to the injectors with the fuel.
How bad is petrol in a diesel? Four scenarios our engineers see around Enfield Lock
Fuelled, and not started: nothing beats it. Being on a forecourt is what makes this the case: elsewhere, the car has been driven there to begin with. With the petrol kept in your tank alone, it's drained and purged right where it stands, and nothing more is needed.
The ignition turned on, or a short start. Once primed, the fuel system has pulled petrol from the tank up to the fuel filter and the lines. That's generally still an easy task — a drain, a flush, and your filter seen to.
Those few miles driven were your pump labouring on fuel diluted by petrol the whole way. The work is your tank, your lines, the filter and clean fuel through the entire system, and how hard the car was driven matters as much as how far. The school run to Prince of Wales Primary School is one thing. Very different once more: a trip to London, under 15 miles away, or any miles on the M25, under a mile from Enfield Lock, where your engine never stopped working hard.
It protested, and only then stopped: smoke, knocking, a throttle gone soft, an idle gone uneven. The fuel isn't acting like diesel any more, and your motor is saying so. Whether it is the verge on Salisbury Road, a lay-by or a side street, stop there and leave it. Long-term damage is very uncommon when a vehicle is stopped soon, and the drain and flush that still come first deal with it.
Petrol in a diesel stories Enfield Lock motorists hear
Myth: topping up to full with diesel makes it fine. It does not. Topping up takes out nothing; it gives you a fuller tank of the same mix. The assumption behind the advice — that diesel fuel systems tolerate petrol by percentage — is wrong.
If anything, the reverse holds. Myth: "A newer diesel can cope with a bit of petrol." Finer components and higher pressure are how a newer diesel runs its fuel, and that makes the protection count more, not less.
The myth that catches motorists out: if it starts and drives, it must be unharmed. Diesel in a petrol motor normally leaves a motor that will not run: the driver stops, and so does the damage. A diesel fed petrol normally starts, idles and drives away as though nothing has happened, while the pump grinds. Running isn't the same as fine.
"A drop of two-stroke oil and drive it home" — a myth, taken from a fix from years ago, for a distinct problem. It doesn't put back what petrol has thinned, and the petrol is still in your tank later.
Once your engine has run, part of the petrol sits in the fuel filter and the fuel lines, not the tank — and the next start pulls it right back through your pump. So the myth "drain the tank yourself and you are sorted" doesn't stand up. It is also really hazardous to drain petrol into a can by the roadside.
Why petrol in a diesel happens at all
It's rarely carelessness, and no one does it on purpose. One way only, since of the nozzles: the narrower petrol one slips inside a diesel filler with almost no resistance, whereas the diesel one mostly will not fit a petrol car. That is how the forecourt makes it simple.
It occurs when routine and your car stop matching. Courtesy car, hire car, or a motor that is brand new. A household with one petrol and one diesel on the driveway. Your ordinary forecourt, its pumps now in a different order. A train to catch, and a rushed fill en route to the nearest station. A new-to-you diesel Renault Megane, its first fuelling, and a driver used to petrol: exactly when it happens. With rain, a call arriving, or children to deal with, your hand simply does what it always has.
Enfield Lock motorists: how to prevent petrol in a diesel next time
- Not every forecourt in the UK follows green for unleaded and black for diesel, though most usually do. Check the petrol pump's label; the colour is only a hint.
- Many vehicles state the fuel type inside the filler flap or on the cap, so check there on the first fill in a motor you don't know.
- A coloured fob or a sticker on the diesel's key achieves more than any amount of intending to remember, in a house with one of each.
- "Diesel", aloud, before you pick up the nozzle — each time a new or hired car needs its first tank. It sounds silly. It works.
- 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.
- Up to a point, a misfuel inhibitor helps: some diesels come with a filler designed to refuse a petrol nozzle, and aftermarket devices are available for the rest. Treat it as a safety net, then keep checking the pump.
- Stop the moment you notice. Less petrol inside the tank makes a thinner mixture. It doesn't change what to do next, which is still not to fire it up.
Petrol already in a diesel in Enfield Lock? Start here
Short and simple, then, is the order of things. Do not switch your ignition on, and do not crank it. Ask the staff to help you push it away from the pump if you are still at the forecourt, whether that's Esso Express or somewhere else. Next, 0333 366 0103. We will ask what got in, roughly how much, and if it has been run.
If it was AdBlue instead of petrol, say so. That's a separate issue — corrosion and deposits and not lost lubrication — and it has its own page for Enfield Lock.
Why one petrol in a diesel task in Enfield Lock costs more than another
A fair single price does not exist here: four scenarios, four separate jobs. The situation itself does most of the work of moving the cost. Two things follow that: the petrol that got in as a share of what your tank holds, then the spot your car is in and whether our van can reach it safely.
What was put in, how much, and whether it's run — three queries we ask before quoting, not after, for precisely that reason. A range turns into a straight figure once those answers are in.
About Enfield Lock
Enfield Lock is a suburban area in the London Borough of Enfield, situated on the banks of the River Lea at an elevation of around 17 metres. Enfield Lock is located approximately 12 miles north of central London, with nearby places including Enfield Island Village and Freezy Water. Enfield Lock is characterized by its predominantly flat-type housing and a population of around 8953 residents. Enfield Lock sits within a wider urban context, with the city of London being the nearest major city, about 11 miles away.
Enfield Lock and Greater London: where our fuel drain cover reaches
Enfield Lock rests in the EN postcode area, and the vans that answer petrol in diesel call-outs there work the spots near it as well — Enfield Island Village, Freezy Water and Enfield Wash among them. The vehicle does not 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.
Still at the pump in Enfield Lock?
Then, you could not be in a better spot. Keep it off. Call.