Hepthorne Lane: Petrol in a Diesel Car? How Worried to Be
Far less than you likely are, if it hasn't been started. Petrol resting in a diesel tank does nothing to your motor until something draws it through your fuel system — the ignition priming your pump, the starter, or the drive on its own. So the fair answer to the first query everyone in Hepthorne Lane asks, "have I wrecked it?", is normally no. To keep the car like that, phone Petrol in Diesel then leave the engine switched off. The remainder of this page explains what petrol really does to a diesel, how to judge how far it has got, and how to make sure it doesn't happen to you again.
Petrol in a diesel: what does it do to your engine?
Two tasks fall to diesel on its route through a motor. Before it burns, it protects — and then it burns. Very fine gaps are built into your injectors and the high-pressure pump, and only your diesel running through stops those surfaces grinding together.
Of these two jobs, petrol manages the first badly and the second never. It is runnier than diesel and takes away the protection the system depends on, so a pump running on a petrol blend 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.
Seen together, they show what shape the problem has. It is movement that does the harm, not contact. Where the petrol is only inside your tank, it's a fault of fuel, nothing more. After the pump has been running on that petrol, a mechanical issue has started: anything shed by a pump that is wearing is carried onward to the injectors with the fuel.
Four situations our technicians see in Hepthorne Lane: how serious is petrol in a diesel?
The best case there is: filled up, never started. At a forecourt, and really only there, the petrol is still limited to your tank — because anywhere else your car was driven to reach it. The job is emptying and purging on the spot.
Your ignition turned on, or a short start. Once primed, your system has pulled petrol from your tank up to the filter and your lines. That's normally still a straightforward task — a drain, a flush, and the fuel filter dealt with.
Some miles driven, and your pump has spent each of them labouring on thinned fuel. How hard the car was driven counts as much as how far, and this work covers the tank, the lines, the filter and fresh fuel through the entire circuit. On the school run to North Wingfield Primary and Nursery Academy, the miles is short. Any miles on the M1, under 3 miles from Hepthorne Lane, means the engine working hard throughout, and a run to Sheffield, under 15 miles away, makes a very different task as well.
It protested, and only then stopped: smoke, rattling, a throttle gone soft, an idle gone ragged. The engine is telling you the fuel is no longer acting like diesel. Pull up wherever you are — the verge on Glebe Gardens, a lay-by, a side street — then leave the vehicle there. What goes first is still the fuel drain and flush, and that sorts it out, with lasting damage very rare when a car is stopped early.
Petrol in a diesel stories Hepthorne Lane motorists hear
Myth: topping up to full with diesel makes it fine. It does not. Nothing is removed by topping up — you're left with a fuller tank, still the same mixture. Percentage isn't how a diesel fuel system copes with petrol, however much that guidance assumes.
Myth: a newer diesel copes with a bit of petrol. If anything, the opposite. At higher pressure, through smaller parts: that is how a current diesel moves its fuel, so the protection counts for more, not less.
This is the one that catches people. Myth: "If it starts and drives, there's no damage done." A petrol engine fed diesel generally won't run, so the motorist stops and the damage stops with them. Nothing looks to have happened when a diesel fed petrol fires up, ticks over and drives away, as it usually will; meanwhile the pump grinds. Being able to run isn't the same as being fine.
Not so: a two-stroke additive makes it safe to drive home. It was an old fix, meant for another fault. It does not put back what petrol has thinned, and that petrol is still inside your tank later on.
Myth: "Drain that tank yourself and you're sorted." After the engine has run, some of the petrol is no longer in that tank: it's in the filter and the lines, and it goes straight back through your pump on the next start. It is also truly dangerous to drain petrol into a can at the kerbside.
Why petrol in a diesel happens so easily
On purpose? Never. Through carelessness? Seldom, if ever. A diesel nozzle mostly won't go into a petrol motor, yet the smaller petrol nozzle goes into the filler of a diesel almost without resistance — so forecourts make this one mistake easy, and just in one direction.
The moment routine stops matching the vehicle is the moment it occurs. A motor that is new to you — hired, on loan as a courtesy car, or just bought. Households running one of each, petrol and diesel. A forecourt you know, but with its pumps laid out differently. Racing for a train at Chesterfield and filling up en route. A new-to-you diesel Renault Megane, its first fuelling, and a driver used to petrol: exactly when it takes place. With rain, a call arriving, or a car full of children to deal with, the hand just does what it always has.
Next time you fill up around Hepthorne Lane: avoiding petrol in a diesel
- Not every forecourt in the UK follows green for unleaded and black for diesel, even if most generally do. Read the pump's label; the colour is just a clue.
- In a vehicle you do not know, look inside the flap over the filler or at the cap before your first fill: plenty of motors state the fuel there.
- Good intentions count for less than a sticker or a fob in a bright colour on your diesel's key if a household has one of each. So label it.
- Before the nozzle comes off the petrol pump the first time you fuel a hired or new motor, say "diesel" aloud. Daft, yes, but it does the trick.
- Put the phone away. This is an easy mistake to make while you are thinking about something else.
- Up to a point, a misfuel inhibitor helps: some diesels have a filler designed to block a petrol nozzle, and add-on devices are available for the rest. Treat it as a backstop, and keep checking the petrol pump.
- Noticing it mid-fill? Stop at once. A thinner mix results from less petrol inside the tank, yet your next step remains the same: don't fire it up.
Already put petrol in a diesel around Hepthorne Lane?
Short and simple, then, is the order of things. Starting it is out, and so is turning on your ignition. The attendants on the forecourt — whether at The Co-operative itself or wherever you filled up — will usually help roll it away from the pump if you ask. What got in, about how much, and whether it's run: tell us that when you ring 0333 366 0103.
AdBlue, not petrol? Then say so. Corrosion and deposits, not lost lubrication, make it a different problem — Hepthorne Lane has a page just for it.
What makes one Hepthorne Lane petrol in a diesel job cost more than the next
There's no honest single quote for this, since the four scenarios above are four different jobs. Which of them you're in is mostly what moves your cost. After that it's the proportion — how much petrol was put in against how much the tank holds — and after that where your car is and whether a technician can reach it safely.
What went in, how much, and if it has run — three queries our engineers ask before quoting, not after, for precisely that reason. A range turns into a straight figure once the replies are in.
About Hepthorne Lane and where it is
Hepthorne Lane is a locality situated in a riverside setting in Derbyshire, with an elevation of around 132 metres. Hepthorne Lane lies near several nearby places, including Egstow, North Wingfield, and Danesmoor, and is approximately 14.6 miles from the city of Sheffield. Hepthorne Lane has a population of around 1761 people, predominantly living in detached housing. Hepthorne Lane is also relatively distant from London, at a distance of 127.1 miles.
Hepthorne Lane and Derbyshire: where our fuel drain cover runs
Our teams answering petrol in diesel call-outs in Hepthorne Lane, in the S postcode area, also work the places near it, Egstow, North Wingfield and Danesmoor included. No need to move your vehicle to us. Forecourts, supermarket car parks, lay-bys and your own drive are all locations we drain.
Hepthorne Lane: still at the pump?
Then, you couldn't be in a better position. Keep it turned off, then ring.