Should You Worry? Petrol in a Diesel Car in Somers Town
Less than you probably are, if it hasn't been started. Everyone around Somers Town starts with "have I ruined it?", and the honest answer is usually no: petrol left inside your tank of a diesel stays harmless until priming, cranking or driving pulls it into the system. Petrol in Diesel is who to phone, with your engine left off, so it stays that way. 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.
Your engine and petrol in a diesel: what goes on
On its way through an engine, diesel has two tasks. Lubricating comes before burning; it does both. Extremely fine gaps are built into the fuel injectors and your high-pressure pump, and just the diesel flowing through stops those surfaces grinding together.
Badly at the first, not at all at the second: that is petrol. The knocking 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 out the protection your system depends on, and any pump working on that mixture is wearing itself.
The shape of the issue is plain once you put those together. Not contact but circulation is what does the harm. Where the petrol is only inside the tank, it's a fault of fuel, nothing more. Whatever a worn pump sheds goes on, carried by your fuel, into the injectors further along, which is why a pump that has been working on the petrol is where a mechanical issue starts.
Petrol in a diesel in Somers Town: how serious is it? Four situations
Filled up, and never started: no case is better. Being on a forecourt is what makes this the case: elsewhere, the car has been driven there to begin with. With that petrol held in that tank alone, it's cleared and flushed on the spot, and nothing more is needed.
Started for a second, or only the ignition on. Petrol has come out of that tank and got to your filter and your lines, since the system has been primed. That's usually still a simple task — a drain, a flush, and the filter seen to.
A few miles driven, and your pump has spent every one of them working on thinned fuel. Tank, lines, filter, then fresh fuel run through the entire circuit: that is the work, and the way your car was driven matters as much as the mileage. Short trips, such as the school run to Ark Ayrton Primary Academy, are one thing. Getting as far as Portsmouth, under a mile away, makes a very different task — as does any mileage on the M275, under a mile from Somers Town, with your engine labouring hard the whole time.
Driven on till it complained — knocking, smoke, a lumpy idle, a dead throttle. What you are hearing is the motor signalling fuel that no longer behaves like diesel. Whether it is the verge on Hyde Park Road, a lay-by or a side road, stop there and leave it. What comes first is still the drain and flush, and that sorts it out, with lasting damage very uncommon if a vehicle is pulled over early.
Somers Town motorists and the petrol in a diesel myths they hear
Myth: "Fill it the rest of the way with diesel and it'll be fine." It will not. Topping up takes out nothing; it gives you a bigger tank of the same mix. The idea behind that guidance — that diesel fuel systems accept petrol by percentage — is wrong.
"Modern diesels can handle a little petrol" — a myth, and closer to the reverse. More precise parts and higher pressure are how a newer diesel runs its fuel, and that makes the lubrication count more, not less.
"It starts, it drives, and so no harm done" — the myth that trips up more motorists than any other. The motorist of a petrol engine fed diesel normally stops, since it will not run, and the damage stops there. Feed petrol to a diesel and it generally fires up, ticks over and drives away as if nothing has happened — all while its pump is wearing. Being able to run isn't the same as being fine.
Myth: "Add some two-stroke oil and drive the car home." It's an outdated fix for a different issue. What petrol has weakened stays weakened, and that petrol stays in the tank anyway.
If your engine has run, part of that petrol sits in the fuel filter and your lines, not your tank — and your next start sends it straight back through your pump. So the myth "drain the tank yourself and you're sorted" doesn't stand up. Also, a can of petrol drained by the roadside is truly dangerous.
How petrol ends up: petrol in a diesel
On purpose? Never. Through carelessness? Rarely, if ever. A diesel nozzle mostly will not fit a petrol vehicle, yet the smaller petrol nozzle goes into the filler of a diesel almost without resistance — so forecourts make this one mistake simple, and only in one direction.
It occurs when routine and the vehicle stop matching. Hire cars, courtesy cars, and cars that are new to you. Households running one of each, petrol and diesel. A forecourt you know, but with its pumps arranged differently. Rushing for a train outside Portsmouth & Southsea and fuelling up en route. The first fill-up in a diesel Volkswagen Golf after years of driving petrol is exactly the moment it occurs. With rain, a call coming in, or children to deal with, the hand just does what it has always done.
Next time you fill up in Somers Town: preventing petrol in a diesel
- Green for unleaded and black for diesel is normal in the UK — yet not on every forecourt. Trust the label on the pump, not the colour.
- In a car you don't know, look inside the flap over your filler or at the cap before your first fill: many cars state the fuel there.
- One of each in the household? Mark the key to your diesel — a bright fob, a sticker — because intending to remember is not enough.
- Before the nozzle comes off the pump the first time you fuel a hired or new motor, say "diesel" aloud. Silly, perhaps, yet it does the trick.
- Whilst you are thinking about something else, this is an easy mistake to make — so put your phone away.
- Up to a point, a misfuel inhibitor helps: some diesels have a filler built to refuse a petrol nozzle, and aftermarket devices are available for the remainder. Count it as a safety net, then keep reading the pump.
- Noticing it halfway? Stop at once. A weaker mixture results from less petrol inside that tank, yet the next step remains the same: don't fire it up.
Put petrol in a diesel in Somers Town already?
Then the order of things is brief. Don't crank it, and do not turn the ignition on. Yet on the forecourt, at Esso or anywhere else? Ask the staff to help you roll the vehicle away from the pump. Next, 0333 366 0103. We'll ask what was put in, about how much, and if it has been run.
If it was AdBlue and not petrol, say so. That is a separate fault — corrosion and deposits instead of lost lubrication — and it has its own page for Somers Town.
One petrol in a diesel task in Somers Town costs more than another. Why?
There's no honest single price for this, because the four scenarios above are four different jobs. Which of them you are in is mostly what moves the cost. Two things come after that: the petrol that was put in as a proportion of what that tank takes, then the spot the vehicle is in and whether our van can get to it safely.
Three questions come first, before quoting, rather than after — what went in, how much, has it run — and this is the reason. With those answers, there is a straight figure instead of a range.
About Somers Town itself
Somers Town is a suburban area located on the coast of Hampshire, situated near the city of Portsmouth. Somers Town sits at a low elevation of around 7 metres, with its predominant housing being flats. Somers Town is close to nearby places such as Fratton and Portsea, and is approximately 64 miles from London.
Somers Town and Hampshire: where our fuel drain cover reaches
Our vans answering petrol in diesel calls around Somers Town, in the PO postcode area, equally work the spots near it, Portsmouth, Fratton and Portsea included. The car does not need to move to us: our technicians drain on a forecourt, in a supermarket car park, in a lay-by or on your own drive.
Somers Town: still at the pump?
Then you are in the best place there is. Call, and keep it switched off.