Portobello: Petrol in a Diesel Car? How Worried to Be
Unstarted? Then less worried than you probably are. Petrol resting in a diesel tank does nothing to your motor until something pulls it through the fuel system — your ignition priming your pump, your starter, or driving itself. So the truthful answer to the first question anyone in Portobello asks, "have I ruined it?", is normally no. To keep the vehicle that way, call Petrol in Diesel and leave the motor alone. The remainder of this page explains what petrol actually does to a diesel, how to tell how far it has got, and how to make sure it doesn't happen to you a second time.
Petrol in a diesel: what does it do to the engine?
Passing through a motor, diesel is doing two things at the same time. Before it ignites, it lubricates — then it combusts. Designed to very fine tolerances, the fuel injectors and the pump depend on the diesel flowing through them to stop their surfaces wearing against one another.
Petrol does the first task badly and the second not at all. A pump working on a petrol mix is wearing itself out, because petrol is runnier than diesel and strips out the lubrication your fuel system relies on. Petrol is also designed to resist igniting under compression — the reverse of what a diesel wants from its fuel — and that is where the knocking starts.
Put these together and the shape of the trouble is clear. The damage is done by circulation, not by contact. Any tank with petrol in it is a fuel fault. Whatever a worn pump sheds goes on, carried by your fuel, into your injectors further along, which is why a pump that has worked on the petrol is where a mechanical problem begins.
Portobello, petrol in a diesel: four situations, from mild to major
Filled up, and never started: nothing beats it. At a forecourt, and truly only there, the petrol is still confined to that tank — since anywhere else the car was driven to reach it. The task is emptying and cleaning on the spot.
Ignition on, or started for a moment. Once primed, the system has pulled petrol from your tank up to the fuel filter and the fuel lines. That is usually still an easy task — a drain, a flush, and the filter seen to.
The pump now worked a few miles on thinned fuel — that is what driving the vehicle meant. Tank, lines, filter, then clean fuel run through the entire system: that is the work, and the way the car was driven counts as much as the miles. Driving the children to Sandal Magna Community Academy is one sort of trip. A run as far as Wakefield, under 3 miles away, is a very different job. So is any mileage on the M1, under 3 miles from Portobello, where the engine has been working hard throughout.
Rattling, a lumpy idle, smoke, a throttle gone soft: driven till it complained. The engine is telling you the fuel is no longer behaving like diesel. Stop on the spot — on the verge on Duke Of York Avenue, at the kerb, down a side road — and don't move it again. The drain and flush-through still go first, and they take care of it: if a car is pulled over early, lasting damage is very unusual.
Stories Portobello motorists hear about petrol in a diesel
Myth: topping up to full with diesel makes it fine. It doesn't. Nothing is removed when you top up — your tank simply carries more of the same blend. The idea behind that guidance — that diesel fuel systems tolerate petrol by percentage — is wrong.
If anything, the reverse is true. Myth: "A modern diesel can cope with a bit of petrol." A newer diesel runs its fuel through smaller parts at higher pressure, which makes the lubrication matter more, not less.
Myth: "If it starts and drives, there's no harm done." This is the one that fools people. Diesel in a petrol motor usually means a motor that won't run: the motorist stops, and so does the damage. While the pump grinds, a diesel fed petrol usually starts, ticks over and drives away as if nothing has happened. 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 problem. What petrol has thinned stays diluted, and the petrol stays inside that tank regardless.
Myth: "Drain that tank yourself and you are sorted." Once your engine has been run, some of the petrol is no longer in your tank: it's in the fuel filter and your lines, and it goes right back through the pump on your next start. Besides, petrol cleared into a can by the road is genuinely hazardous.
How petrol ends up: petrol in a diesel
A careless moment is seldom the cause, and nobody means to do it. The petrol nozzle is the slimmer of the two and slides into a diesel filler with almost no resistance; a diesel nozzle generally won't go into a petrol vehicle at all. The forecourt makes it simple, and the slip runs one way.
When routine and the car stop matching, it occurs. Any car that's new to you — a hire car, on loan as a courtesy car, or just bought. A household with one petrol and one diesel on the drive. A familiar forecourt with the pumps in a different order. Fuelling up in a rush en route to Sandal & Agbrigg, with a train to catch. The first fill-up in a diesel Volkswagen Golf after years of driving petrol is precisely the moment it occurs. Add rain, a phone call or a back seat full of children, and your hand repeats what it has always done.
Next time you fill up around Portobello: avoiding petrol in a diesel
- The label is what matters, and so check the petrol pump instead of the colour: in the UK unleaded handles are usually green and diesel black, yet not on each forecourt.
- Check the filler flap. Many vehicles state the fuel type inside the flap or on the cap. Look at it on the first fill in any motor you don't know.
- Good intentions count for less than a sticker or a fob in a vivid colour on the diesel's key when a home has one of each. So mark it.
- Before the nozzle leaves the pump the first time you fuel a hired or new vehicle, say "diesel" aloud. Daft, yes, but it does the trick.
- Mistakes like this are easy to make whilst your mind is on something else, and so the phone goes away.
- Add-on devices are available for cars without one, and some diesels are built with a filler that will not accept a petrol nozzle. Useful — but a safety net at best, never a reason to stop checking the label.
- Stop as soon as you notice. Less petrol in the tank makes a thinner mix. It doesn't change what to do next, which is still not to fire it up.
Portobello: already put petrol in a diesel?
Short and simple, then, is the order of things. Do not fire it up, and don't turn the ignition on. Ask the attendants to help you roll it clear of the pump if you are still at the forecourt, whether that's BP or anywhere else. Call 0333 366 0103 next, with three answers — your fuel, the rough amount, and whether it's run.
If it was AdBlue rather than petrol, say so. That's a different fault — corrosion and deposits instead of lost lubrication — and it has its own page for Portobello.
Portobello petrol in a diesel jobs: why one costs more than another
A fair single price doesn't exist here: four scenarios, four separate tasks. What moves the cost is chiefly which of them you are in. Two things come after that: the petrol that went in as a share of what your tank takes, then the spot your car is in and whether a van can reach it safely.
Ahead of any quote, not after, we ask three questions: the fuel that got in, the amount, and if it's run. That is why. A range turns into a straight figure when those replies are in.
About Portobello and its setting
Portobello is a suburban area in West Yorkshire, situated on the riverside near Wakefield, with a mix of terraced housing and local amenities. Portobello sits at an elevation of 31 metres, close to the nearby places of Sandal, Belle Isle, and Agbrigg. Portobello is located approximately 1.4 miles from Wakefield city centre, making it a convenient residential area. Portobello has a population of around 5805 people, according to recent estimates.
Across West Yorkshire and around Portobello: fuel drain cover
Sandal, Belle Isle and Agbrigg are among the locations near Portobello that the same vans work, answering petrol in diesel jobs across Portobello's WF postcode area. Our engineers drain wherever the vehicle is — your own driveway, a lay-by, a supermarket car park, a forecourt — so it does not have to come to us.
Portobello: still at the pump?
Then, you could not be in a better place. Keep it off. Call.