How Worried Should You Be? Petrol in a Diesel Car in North End
Unstarted? Then less anxious than you likely feel. Petrol sitting in a diesel tank does nothing to your motor till something draws it through the fuel system — the ignition priming the pump, your starter, or driving on its own. So the fair answer to the first query everyone in North End asks, "have I ruined it?", is usually no. To leave the car that way, phone Petrol in Diesel and leave the motor alone. What petrol actually does to a diesel, how to judge how far it has travelled, and how to stop it from happening again: that's the rest of this page.
Inside the motor: what petrol in a diesel does
On its way through a motor, diesel has two jobs. Before it ignites, it protects — and then it combusts. Extremely fine tolerances go into the injectors and the high-pressure pump, and only your diesel flowing through stops those surfaces grinding together.
The second task petrol does not do at all, and the first it does badly. A pump running on a petrol blend is wearing itself out, since petrol is runnier than diesel and takes away the protection your fuel system depends 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 rattling comes.
Taken together, they show the shape the issue has. The damage is done by movement, not by contact. All a tank with petrol in it amounts to is a fuel fault. Whatever a worn pump sheds goes on, carried by the fuel, into the injectors downstream, which is why a pump that has worked on the petrol is where a mechanical issue begins.
How bad is petrol in a diesel? Four situations our engineers see around North End
Fuelled but not once started — the best it gets. That petrol is inside your tank and just your tank, and the task is a drain and a flush where the car stands. This is the one situation that can only truly happen at a forecourt, since anywhere else your car has been driven to get there.
Ignition on, or started for a second. With the system primed, the fuel lines and filter now contain petrol that came from the tank. That's usually still an easy task — a drain, a flush, and the fuel filter seen to.
The pump now worked a couple of miles on thinned fuel — that's what driving the vehicle meant. The work is the tank, your lines, the filter and fresh fuel through the entire system, and how hard the vehicle was driven matters as much as how far. Short trips, like the school run to Halsford Park Primary School, are one matter. Driving as far as Brighton and Hove, under 25 miles away, makes a very different task — as does any distance on the M23, under 5 miles from North End, with the motor labouring hard all the way.
It complained, and only then stopped: smoke, rattling, a throttle gone soft, an idle gone ragged. The fuel is not acting like diesel any more, and your motor is telling you. Stop where you are — on the verge on Imberhorne Lane, at the kerb, down a side road — and do not move it. A car stopped quickly very seldom has lasting damage, because the drain and the flush, which still go first, sort it out.
What North End motorists get told about petrol in a diesel — and the stories in it
It will not be fine. The myth: "Fill it the rest of the way with diesel and it will be." Nothing is removed by topping up — you're left with a fuller tank, still the same mixture. That advice supposes a diesel fuel system handles petrol by percentage. It doesn't.
If anything, the reverse holds. Myth: "A modern diesel can cope with a bit of petrol." A newer diesel sends its fuel through finer components at higher pressure, which makes the lubrication count more, not less.
This is the one that catches motorists. Myth: "If it starts and drives, there is no harm done." Feed diesel to a petrol engine and it generally 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, as it usually does; meanwhile the pump wears. Being able to run isn't proof of being fine.
An outdated workaround for a distinct fault is behind this one. Myth: "Add some two-stroke oil and drive it home." It does not put back what petrol has diluted, and the petrol is still inside that tank later.
Once the motor has been run, part of that petrol sits in the filter and the lines, not that tank — and the next start sends it straight back through the pump. So the myth "drain your tank yourself and you are sorted" doesn't hold. Besides, petrol emptied into a can by the road is genuinely dangerous.
How does petrol in a diesel occur?
Nobody does it on purpose, and it's seldom carelessness. The forecourt makes it easy: the petrol nozzle is the narrower of the two, and it slips into a diesel filler with almost no resistance, while a diesel nozzle generally will not go into a petrol vehicle at all. So the slip runs one way.
It occurs when habit and the car stop matching. A new vehicle, a hire car or a courtesy car. Households running one of each, petrol and diesel. The pumps in a different order on a well-known forecourt. A rushed fill on the way to East Grinstead with a train to catch. Years of petrol vehicles behind you, a diesel Volkswagen Golf in front of you on the forecourt for its first tank — that's when. With rain, a call arriving, or a car full of children to deal with, your hand simply does what it always has.
North End drivers: how to avoid petrol in a diesel next time
- The label is what matters, so read the pump rather than the colour: in the UK unleaded handles are usually green and diesel black, yet not on each forecourt.
- In a vehicle you do not know, look inside the flap over the filler or at the cap before your first fill: many cars state the fuel there.
- Good intentions do less than a sticker or a fob in a bright colour on the diesel's key if a household has one of each. So label it.
- "Diesel", aloud, before you lift the nozzle — every time a new or hired car needs its first tank. It sounds silly. It works.
- Mistakes like this are simple to make while your mind is on something else, and so the phone goes away.
- Up to a point, a misfuel inhibitor helps: some diesels come with a filler built to reject a petrol nozzle, and add-on devices are available for the rest. Count it as a backstop, then keep checking the pump.
- Less petrol means a weaker blend, so stop as soon as you realise — though remembering that your next stage is unchanged. It's still not to fire it up.
Put petrol in a diesel around North End already?
Then, there is only a short order of things. Leave it unstarted, with the ignition switched off as well. If you are still on the forecourt — BP or anywhere else — ask the attendants to help you roll it clear of the pump. What got in, roughly how much, and whether it's run: tell us that when you call 0333 366 0103.
Corrosion and deposits are the problem with AdBlue, where petrol means lost protection. So if it was AdBlue, say so — and read its own North End page.
North End petrol in a diesel jobs: why one costs more than another
There is no fair single price for this, because the four scenarios above are four separate tasks. Which of them you're in is chiefly what shifts your cost. Two things follow that: the petrol that got in as a proportion of what your tank holds, then the spot your car is in and whether a technician can reach it safely.
Before any quote, not after, we ask three questions: the fuel that went in, the amount, and whether it's run. That is why. Those replies are what turn a range into one firm number.
About North End itself
North End is a suburban area in West Sussex, situated near the riverside and surrounded by nearby places such as Felbridge and Baldwins Hill. North End sits at an elevation of 98 metres, with detached housing being the predominant type of accommodation in the area. North End is located approximately 25.9 miles from London and 22.2 miles from the city of Brighton and Hove. North End has a population of around 2237 residents.
Fuel drain cover across West Sussex, North End included
North End sits in the RH postcode area, and the vans that answer petrol in diesel call-outs there work the places around it as well — Felbridge, Baldwins Hill and Blackwell among them. A forecourt, a supermarket car park, a lay-by or your own driveway are all spots our engineers work, and the car does not need to come to us.
At the petrol pump in North End, right now?
In that case, you couldn't be in a better spot. Ring, and leave it turned off.