How Worried Should You Be? Petrol in a Diesel Car in Furnace Green
Not started? Then less worried than you probably are. "Have I wrecked it?" is the first thing anyone around Furnace Green asks, and the honest answer is normally no, since petrol left in a diesel tank harms nothing until it is dragged through your fuel system — by ignition priming, by the starter, or by being driven. Leave your engine off then phone Petrol in Diesel — that keeps it like that. Keep reading 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 don't do it again.
What petrol in a diesel does to the motor
On its way through a motor, diesel has two tasks. Oiling comes before burning; it does both. Very fine tolerances go into the injectors and the high-pressure fuel pump, and only the diesel running through keeps their surfaces from grinding together.
Of these two jobs, petrol handles the first badly and the second never. The clattering comes from petrol being designed not to ignite when compressed, which is exactly the reverse of what a diesel needs. On top of that it is runnier than diesel, it strips away the lubrication the system rests on, and any pump working on such a mixture is wearing itself.
The shape of the issue is plain when you put those together. Not contact but movement is what does the damage. Petrol in the tank is a fuel issue. The start of a mechanical problem is a pump that has been running on that petrol — and whatever a worn pump sheds moves on with the fuel to the fuel injectors beyond it.
Four scenarios we see around Furnace Green: how serious is petrol in a diesel?
Filled up, and not started: nothing beats it. At a forecourt, and truly only there, that petrol is still confined to your tank — since anywhere else your car was driven to reach it. The job is emptying and cleaning on the spot.
The ignition turned on, or a brief start. Petrol has left your tank and got to your filter and the fuel lines, since your system has been primed. Usually nothing more than emptying, rinsing and seeing to the filter, and so still straightforward.
Those few miles on the road meant your pump working on fuel thinned by petrol the whole way. The work is the tank, your lines, the fuel filter and clean fuel through the entire circuit, and how hard your car was driven counts as much as how far. Driving the children to St Andrew's CofE Primary School is one sort of trip. Any distance on the M23, under 3 miles from Furnace Green, means the motor working hard throughout, and a run to Brighton and Hove, under 25 miles away, is a very different job as well.
Rattling, a ragged idle, smoke, a throttle gone soft: driven till it complained. The fuel is not behaving like diesel any more, and your motor is saying so. Stop where you are — on the verge on Waterlea, at the kerb, down a side road — and don't move it. Long-term damage is very uncommon when a vehicle is stopped soon, and the drain and flush that still come first take care of it.
Furnace Green motorists and that petrol in a diesel stories they hear
"Top it up the rest of the way with diesel and it will be fine" — a myth. It will not. A bigger tank of the same mixture is all you get, since topping up removes nothing. That advice supposes a diesel fuel system handles petrol by percentage. It doesn't.
"Modern diesels can handle a little petrol" — a myth, and nearer the opposite. A current diesel runs its fuel through finer components at higher pressure, which makes the protection matter more, not less.
"It starts, it drives, so no harm done" — the myth that catches more motorists than any other. The motorist of a petrol motor fed diesel usually has no choice but to stop, since it will not run, and the damage stops there. A diesel fed petrol normally starts, ticks over and drives away as if nothing has happened, whilst the pump grinds. Fine and running aren't the same at all.
Not so: a two-stroke additive makes it safe to drive home. It is an old workaround, meant for another problem. None of what petrol diluted gets put back by it — and afterwards, your tank still holds the petrol.
The next start sends petrol back round the pump out of the lines and the fuel filter, where some of that sits once the motor has been run. That's why a DIY tank drain doesn't sort it — a myth. Clearing petrol into a can by the roadside is also really hazardous.
Why petrol in a diesel happens so easily
Nobody does it on purpose, and it's rarely carelessness. The forecourt makes it simple: the petrol nozzle is the smaller of the two, and it slides into a diesel filler with almost no resistance, while a diesel nozzle mostly won't go into a petrol motor at all. So the slip runs one way.
When habit and the car stop matching, it happens. Hire cars, courtesy cars, and vehicles that are new to you. Households running one of each, petrol and diesel. The pumps in a different order on a familiar forecourt. Racing for a train outside Three Bridges and filling up en route. Exactly the moment it happens: after years of driving petrol, a driver fills a diesel Volkswagen Golf for the first time. 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 Furnace Green: preventing petrol in a diesel
- The label is what counts, and so check the pump rather than the colour: in the UK unleaded handles are usually green and diesel black, but not on each forecourt.
- Check your filler flap. Plenty of cars state the fuel type inside the flap or on the cap. Look at it on your first fill in a motor 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 home with one of each.
- Say it before you lift it. On the first fill in a new or hired car, say "diesel" out loud before you take the nozzle off the pump. It sounds daft and it works.
- Mistakes like this are easy 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 have a filler built to reject a petrol nozzle, and add-on devices are available for the rest. Treat it as a safety net, then keep reading the pump.
- Less petrol makes a thinner mixture, so stop the moment you notice — though remembering that the next step is unchanged. It is still not to start it.
Petrol already in a diesel in Furnace Green? Start here
Short and simple, then, is the order of things. Do not crank it, and don't switch your ignition on. Still on the forecourt, at BP or anywhere else? Ask the attendants to help you roll the car away from the pump. Next, 0333 366 0103. We'll ask what got in, about how much, and if it's been run.
If it was AdBlue instead of petrol, say so. That's a different issue — corrosion and deposits and not lost lubrication — and it has its own page for Furnace Green.
Why one petrol in a diesel job in Furnace Green costs more than another
The four scenarios above are four separate tasks, so no single quote for this would be honest. Which of them you're in is chiefly what moves the cost. Where your car is counts too, and whether our van can safely get to it, after the ratio of petrol to what the tank holds.
Before any quote, not after, we ask three queries: the fuel that was put in, the quantity, and whether it has run. That's why. A range becomes a straight figure once those replies are in.
About Furnace Green
Furnace Green is a suburban area in West Sussex, situated inland at an elevation of 76 metres, and forms part of the larger Crawley urban area. Furnace Green is located near Tilgate, Northgate, and other residential neighbourhoods, and is approximately 19.8 miles from Brighton and Hove. Furnace Green has a population of around 7468 people, predominantly residing in flat-type housing. Furnace Green is also within commuting distance of London, being around 27.6 miles from the capital.
Furnace Green and West Sussex: where our fuel drain cover runs
Furnace Green waits in the RH postcode area, and our teams that answer petrol in diesel calls there work the places around it as well — Tilgate, Northgate and Crawley among them. No need to move your vehicle to us. Forecourts, supermarket car parks, lay-bys and your own drive are all spots where we work.
In Furnace Green and still at the pump?
Then you are in the best position there can be. Keep it off. Ring.