Green Street Green: 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 your motor till something pulls it through your fuel system — the ignition priming your pump, the starter, or the drive itself. So the fair answer to the first query everyone around Green Street Green asks, "have I ruined it?", is generally no. Keep it like that: leave your engine off and call Petrol in Diesel. The rest of this page explains what petrol actually does to a diesel, how to judge how far it has got, and how to make sure it does not happen to you again.
Petrol in a diesel: what does it do to the engine?
On its way through a motor, diesel has two tasks. It combusts, and before it combusts it protects. Built to extremely fine tolerances, the injectors and your pump depend on the diesel flowing through them to stop their surfaces wearing against one another.
The second job petrol does not do at all, and the first it does badly. Being less viscous than diesel, petrol strips away the protection a fuel system needs, so a pump running on the mixture wearing itself. It is equally made to resist igniting under compression — the reverse of what a diesel needs — which is why you get the knocking.
Together, those make the shape of the problem clear. It's movement that does the damage, not contact. All a tank with petrol in it amounts to is a fuel issue. A pump that has been running on that petrol is the beginning of a mechanical one, and whatever a worn pump sheds moves on with your fuel to the fuel injectors further on.
Green Street Green, petrol in a diesel: four cases, from mild to major
Fuelled up, not once started. The best case there is. On a forecourt, and genuinely only there, the petrol is still limited to the tank — because everywhere else your car was driven to get to it. The task is emptying and cleaning on the spot.
Ignition on, or started for a second. Petrol has come out of your tank and got to your filter and your lines, since your system has been primed. Normally little more than emptying, cleaning and sorting the filter, and so still simple.
Driven a few miles. Now the pump has spent these miles labouring on weakened fuel. How hard your car was driven counts as much as how far, and the work takes in your tank, your lines, the fuel filter and clean fuel through the whole system. Driving the children to Greenlands Primary School is one kind of trip. A run as far as London, under 25 miles away, is a very different task. So is any mileage on the M25, under 3 miles from Green Street Green, where your engine has been running hard throughout.
It complained, and only then stopped: smoke, clattering, a throttle gone soft, an idle gone ragged. What you are hearing is your engine signalling fuel that no longer acts like diesel. Stop wherever you are — the verge on Sandbanks Hill, a lay-by, a side street — and leave it where it is. The fuel drain and flush-through still come first, and they sort it out: if a vehicle is pulled over soon, long-term damage is very uncommon.
What Green Street Green drivers get told about petrol in a diesel — and the stories in it
"Top it up the rest of the way with diesel and it will be fine" — a myth. It won't. A bigger tank of the same mix is all it gives, because topping up removes nothing. That advice presumes a diesel fuel system tolerates petrol by percentage. It does not.
Myth: "A current diesel can cope with a bit of petrol." If anything, the opposite. At higher pressure, through smaller components: that's how a newer diesel handles its fuel, so the lubrication counts more, not less.
The myth that catches people off guard: if it starts and drives, it must be unharmed. Any petrol motor fed diesel normally won't run, and so the driver stops and the harm stops with them. Nothing looks to have happened when a diesel fed petrol fires up, ticks over and drives away, as it usually does; meanwhile the pump grinds. Fine and running are not the same thing.
An outdated workaround for a different issue lies behind this one. Myth: "Add some two-stroke oil and drive the car home." What petrol has weakened stays diluted, and that petrol stays in the tank regardless.
The next start draws petrol back round the pump out of the lines and your filter, where some of it sits after your engine has run. That's why a DIY tank drain doesn't leave you sorted — a myth. On top of that, petrol drained into a can by the road is truly hazardous.
Petrol in a diesel: how does it take place?
On purpose? Never. Through carelessness? Rarely, if ever. One way only, since of the nozzles: the narrower petrol one slips inside a diesel filler with almost no resistance, whereas the diesel one mostly won't fit a petrol car. That's how the forecourt makes it straightforward.
The moment routine stops matching the car is the moment it occurs. A new vehicle, a hire car or a courtesy car. Two motors on one driveway, one petrol, one diesel. Your ordinary forecourt, its pumps suddenly in a different order. Racing for a train at Longfield and filling up en route. Years of petrol motors behind you, a diesel Volkswagen Passat in front of you on the forecourt for its first tank — that is when. Add a back seat full of kids, a phone call or rain, and habit wins.
How to prevent petrol in a diesel at your next fill-up in Green Street Green
- The label is what matters, so read the petrol pump rather than the colour: in the UK unleaded handles are normally green and diesel black, but not on every forecourt.
- Many vehicles state the fuel type inside your filler flap or on the cap, and so check there on your first fill in a vehicle you do not know.
- A coloured fob or a sticker on your diesel's key does more than any amount of meaning to remember, for a house with one of each.
- Before the nozzle comes off the petrol pump the first time you fuel a hired or new car, say "diesel" out loud. Daft, perhaps, yet it works.
- Thinking about something else is when this becomes an easy mistake to make, so put the phone away then keep your mind on the petrol pump.
- Up to a point, a misfuel inhibitor helps: some diesels have a filler built to reject a petrol nozzle, and add-on devices exist for the rest. Count it as a backstop, then keep reading the pump.
- Spotting it mid-fill? Stop at once. A thinner mixture follows from less petrol inside the tank, but the next stage stays the same: do not start the car.
Green Street Green: already put petrol in a diesel?
The order of things is brief, then. Don't fire it up, and don't turn the ignition on. The staff on the forecourt — whether at Shell itself or wherever you filled up — will normally help roll it clear of the petrol pump if you ask. What got in, about how much, and if it's run: tell us that when you phone 0333 366 0103.
Say so if it was AdBlue rather than petrol: it's a different issue, with its own page for Green Street Green, since AdBlue brings corrosion and deposits instead of lost lubrication.
What makes one Green Street Green petrol in a diesel job cost more than the next
There is no honest single price for this, because the four situations above are four different jobs. Which of them you are in is chiefly what shifts the cost. The ratio matters next, meaning how much of that tank is petrol, followed by the location of the vehicle and whether reaching it is safe for a technician.
Three queries come first, before quoting, instead of after — what was put in, how much, has it run — and that is the reason. Those answers are what turn a range into one firm number.
About Green Street Green itself
Green Street Green is a small village in Kent, situated inland at an elevation of 33 metres, and is located approximately 18.6 miles from London. Green Street Green has a population of around 513 people and is characterised by predominantly detached housing. Green Street Green is near to other local places such as Grubb Street, St Margarets, and Westwood, and is within commuting distance of London.
Fuel drain cover in Green Street Green and across Kent
Green Street Green waits in the DA postcode area, and the teams that answer petrol in diesel calls there work the spots around it as well — Grubb Street, St Margarets and Westwood among them. Our technicians drain where the car is — your own drive, a lay-by, a supermarket car park, a forecourt — so it never needs to come to us.
At the petrol pump in Green Street Green, right now?
Then, you couldn't be in a better position. Phone, and leave it turned off.