Ubberley: Petrol in a Diesel Car? How Worried to Be
If it hasn't been started, worry less than you probably are. Petrol sitting in a diesel tank does nothing to the motor till something draws it through your fuel system — the ignition priming your pump, the starter, or driving on its own. So the truthful answer to the first query everyone in Ubberley asks, "have I ruined it?", is generally no. Keep it that way: leave the motor off then call Petrol in Diesel. Read on for three things: the effect petrol has inside a diesel engine, the clues of how far it has got, and the way to make sure you never do it again.
Petrol in a diesel: what does it do to the engine?
Passing through an engine, diesel does two jobs at the same time. Lubricating comes before burning; it does both. Extremely fine gaps go into the fuel injectors and the high-pressure pump, and just the diesel flowing through keeps those surfaces from grinding together.
The second task petrol doesn't do at all, and the first it does badly. It is thinner than diesel and removes the protection the fuel system depends on, so a pump running on a petrol mix is a pump wearing itself. And petrol is made to resist igniting under compression, which is the opposite of what a diesel needs from its fuel. That's where the knocking comes from.
The shape of the issue is plain once you put those together. Contact does not do the damage — movement does. Petrol in the tank is a fuel problem. A pump that has been running on that petrol is the beginning of a mechanical one, and whatever a worn pump sheds travels on with the fuel to the injectors downstream.
How serious is petrol in a diesel? Four situations our engineers see around Ubberley
Filled but not once started — the best it gets. On a forecourt, and genuinely only there, that petrol is still limited to your tank — because anywhere else your car was driven to reach it. The task is emptying and flushing on the spot.
The ignition switched on, or a brief start. Petrol has left that tank and got to the filter and the lines, because your system has been primed. Still usually simple: drain, flush, and the fuel filter dealt with.
Driven a few miles. Now your pump has spent those miles running on weakened fuel. How hard the vehicle was driven counts as much as how far, and this work takes in the tank, the fuel lines, the fuel filter and clean fuel through the whole system. On the school run to Maple Court Academy, the mileage is small. Very different again: a run to Stoke-on-Trent, under 3 miles away, or some distance on the M6, under 5 miles from Ubberley, where the engine kept labouring hard.
Driven until it protested. Clattering, an uneven idle, smoke, a throttle that has gone soft. That's your motor telling you its fuel no longer is behaving like diesel. Pull up on the spot — on the verge on Galloway Road, at the kerb, down a side road — and do not move it. What goes first is still the fuel drain and flush, and that deals with it, with long-term damage very unusual if a vehicle is pulled over soon.
What Ubberley people get told about petrol in a diesel — and the stories in it
"Top it up the rest of the way with diesel and it'll be fine" — a myth. It will not. Topping up takes out nothing; it gives you a bigger tank of the same mixture. That advice assumes a diesel fuel system handles petrol by percentage. It doesn't.
Myth: "A current diesel can cope with a bit of petrol." If anything, the reverse. A modern diesel sends its fuel through smaller parts at higher pressure, which makes the protection count more, not less.
The myth that catches people out: if it starts and drives, it must be unharmed. Feed diesel to a petrol engine and it normally won't run, and so the driver stops — and the damage stops with them. Nothing seems to have happened when a diesel fed petrol fires up, ticks over and drives away, which it usually will; meanwhile the pump wears. Running doesn't mean fine.
"A drop of two-stroke oil and drive it home" — a myth, taken from a fix from years ago, for a separate fault. The petrol is still in your tank afterwards, and whatever it has diluted is not put back.
"Drain it yourself and you're sorted" — a myth, because after it's been running some petrol sits in your filter and lines, ready to go straight back through your pump at the next start. Besides, petrol cleared into a can by the road is genuinely risky.
Why petrol in a diesel happens so easily
On purpose? Never. Through carelessness? Rarely, if ever. The forecourt makes it simple: the petrol nozzle is the narrower of the two, and it slides into a diesel filler with almost no resistance, whilst a diesel nozzle generally will not go into a petrol car at all. So the slip runs one way.
The moment routine stops matching your car is the moment it happens. A new vehicle, a hire car or a courtesy car. One petrol and one diesel on the driveway of the same household. The pumps in a different order on a well-known forecourt. A rushed fill en route to Longton with a train to catch. A new-to-you diesel Volkswagen Tiguan, its first fuelling, and a motorist accustomed to petrol: precisely when it happens. With rain, a call arriving, or children to deal with, your hand simply does what it has always done.
Next time you fill up around Ubberley: avoiding petrol in a diesel
- Not every forecourt in the UK keeps to green for unleaded and black for diesel, though most generally do. Read the petrol pump's label; the colour is only a hint.
- In a motor you don't know, look inside the flap over your filler or at the cap before the first fill: many cars print the fuel type there.
- A coloured fob or a sticker on the diesel's key achieves more than any amount of intending to remember, in a home with one of each.
- "Diesel", out loud, before you lift the nozzle — every time a new or hired car gets its first tank. It sounds daft. It does the trick.
- Whilst you are thinking about something else, this is an easy mistake to make — so put your phone away.
- Some diesels come with a filler built to reject a petrol nozzle, and devices you can add are available for vehicles without one. Such an inhibitor helps up to a point — as a safety net, not a reason to stop checking the pump.
- As soon as you notice, stop: less petrol inside your tank makes a thinner blend. What to do next does not change, though — still do not start the car.
Petrol already in a diesel around Ubberley? Start here
The order of things is brief, then. Don't fire it up, and don't switch the ignition on. Ask the staff to help you push it clear of the pump if you are still on the forecourt, whether that's Esso or anywhere else. Next, 0333 366 0103. We will ask what got in, about how much, and if it has been run.
AdBlue, not petrol? Then say so. Corrosion and deposits, not lost protection, make it a different issue — Ubberley has a page all for it.
What makes one Ubberley petrol in a diesel job cost more than the next
A fair single quote does not exist here: four scenarios, four separate tasks. Which of them you're in is chiefly what moves your cost. After that it is the ratio — how much petrol went in against how much the tank takes — and after that where the vehicle is and whether a van can reach it safely.
Three questions come first, before any quote, rather than after — what went in, how much, has it run — and that is the reason. The answers turn a range into a straight figure.
About Ubberley
Ubberley is a suburban area located near Stoke-on-Trent in Staffordshire, sitting at an elevation of 179 metres in the inland West Midlands region. Ubberley is characterised by its semi-detached housing stock and is situated close to nearby places such as Bentilee, Adderley Green, and Ash Bank. Ubberley is approximately 2.3 miles from Stoke-on-Trent and around 133.8 miles from London.
Across Staffordshire and around Ubberley: fuel drain cover
Ubberley waits in the ST postcode area, and the vans that answer petrol in diesel calls there work the spots around it as well — Bentilee, Adderley Green and Ash Bank among them. Our engineers drain wherever the car is — your own driveway, a lay-by, a supermarket car park, a forecourt — so it does not have to come to us.
Ubberley: still at the petrol pump?
No position is better: that's where you are. Turned off it remains; then ring.