Petrol in a Diesel Car in Caenby: How Worried Should You Be?
If it hasn't been started, you can worry less than you probably are. Petrol sitting in a diesel tank does nothing to the engine till something draws it through your fuel system — your ignition priming the pump, your starter, or driving itself. So the truthful answer to the first query everyone in Caenby asks, "have I wrecked it?", is usually no. To leave the car like that, call Petrol in Diesel and leave your motor switched off. Further down, this page sets out what petrol really does inside a diesel, how far it may have got, and how to stop it happening to you again.
The motor and petrol in a diesel: what happens
Passing through an engine, diesel does two things at once. It ignites, and before it ignites it lubricates. Made to very fine tolerances, the injectors and the pump rely on the diesel flowing through them to keep their surfaces from wearing against one another.
Petrol handles the first task badly and the second not at all. The clattering 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 thinner than diesel, it strips away the lubrication the fuel system depends on, and any pump working on that mix is wearing itself.
Put those together and the shape of the issue is plain. It is movement that causes the harm, not contact. Any tank with petrol in it is a fuel fault. A pump that has been labouring on that petrol is the start of a mechanical one, and whatever a worn pump sheds moves on with your fuel to the injectors downstream.
How serious is petrol in a diesel? Four scenarios our engineers see around Caenby
Filled up, and not started: no case is better. The petrol is in that tank and just that tank, and the job is a drain and a flush where your car stands. This is the one scenario that can only really take place on a forecourt, since anywhere else the vehicle has been driven to get there.
Ignition on, or started for a moment. Once primed, the system has drawn petrol out of that tank as far as the fuel filter and the lines. Normally nothing more than clearing, cleaning and sorting your filter, and so still simple.
Driven a few miles. Now your pump has spent these miles working on diluted fuel. Mileage is only half of that; how hard it was driven counts just as much. Either way the work runs to the tank, the lines, the filter and fresh fuel through the whole circuit. Driving the kids to Normanby Primary School is one kind of trip. A run as far as Lincoln, under 15 miles away, is a very different job. So is any distance on the M180, under 15 miles from Caenby, where the motor has been running hard the whole time.
It complained, and only then stopped: smoke, knocking, a throttle gone soft, an idle gone ragged. The fuel is not behaving like diesel any more, and your engine is saying so. Whether it is the verge on Chapel Court, a lay-by or a side road, stop where you are then leave it. The fuel drain and flush-through still go first, and they sort it out: when a car is stopped quickly, lasting damage is very rare.
What Caenby people get told about petrol in a diesel — and the myths in it
Myth: "Fill it the rest of the way with diesel and it will be fine." It will not. Topping up takes out nothing; it gives you a bigger tank of the same mixture. That guidance supposes a diesel fuel system handles petrol by percentage. It does not.
Myth: "A current diesel can cope with a bit of petrol." If anything, the reverse. A modern diesel runs its fuel through more precise components 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 motorists. Any petrol engine fed diesel normally won't run, and so the motorist stops and the harm stops with them. Nothing looks to have happened when a diesel fed petrol fires up, ticks over and drives away, which it usually will; meanwhile the pump grinds. Fine and running are not the same thing.
An old fix for a separate problem is behind this one. Myth: "Add some two-stroke oil and drive it home." What petrol has thinned stays diluted, and that petrol stays in the tank regardless.
The next start sends petrol back round your pump from your lines and the fuel filter, where some of it sits once the motor has run. That's why a DIY tank drain doesn't sort it — a myth. It is also truly dangerous to drain petrol into a can by the roadside.
Why petrol in a diesel occurs at all
It is seldom carelessness, and no one does it on purpose. One way only, since of the nozzles: the narrower petrol one slides inside a diesel filler with almost no resistance, whereas the diesel one mostly won't fit a petrol car. That is how the forecourt makes it simple.
When habit and your car stop matching, it takes place. Hire cars, courtesy cars, and vehicles that are new to you. One petrol and one diesel on the drive of the same household. Your normal forecourt, its pumps now in a different order. Racing for a train outside Market Rasen and filling up en route. The first fill-up in a diesel Skoda Octavia after years of driving petrol is exactly the moment it happens. With rain, a call coming in, or children to deal with, the hand simply does what it has always done.
Avoiding petrol in a diesel next time you fill up around Caenby
- Green for unleaded and black for diesel is usual in the UK — but not on each forecourt. Go by the label on the pump, not the colour.
- In a vehicle you do not know, look inside the flap over the filler or at the cap before your first fill: many cars print the fuel there.
- Good intentions do less than a sticker or a fob in a vivid colour on your diesel's key when a home has one of each. So mark it.
- Say it before you lift it. On your first fill in a new or hired car, say "diesel" out loud before you take the nozzle off the petrol pump. It seems daft and it works.
- Mistakes like this are easy to make while your mind is on something else, so your phone goes away.
- Add-on devices are available for vehicles without one, and some diesels come with a filler that will not accept a petrol nozzle. Useful — but a backstop at best, never a reason to stop checking the label.
- Spotting it mid-fill? Stop there and then. A thinner blend follows from less petrol inside your tank, yet the next stage stays the same: do not start the vehicle.
Already put petrol in a diesel around Caenby?
The order of things is short, then. Don't turn your ignition on, and don't crank it. Still at the forecourt, at the nearest petrol station or anywhere else? Ask the attendants to help you push the car away from the petrol pump. Then ring 0333 366 0103 and tell us what was put in, roughly how much, and if it's run.
If it was AdBlue and not petrol, say so. That is a separate issue — corrosion and deposits rather than lost protection — and it has its own page for Caenby.
Why one petrol in a diesel job in Caenby costs more than another
Four different jobs lie behind the four scenarios above — which is why there's no fair single quote. The situation itself does most of the work of moving your cost. Where the car is matters too, and whether a van can safely reach it, after the share of petrol to what that tank takes.
Three queries come first, before any quote, rather than after — what got in, how much, has it run — and this is the reason. Given those replies, you get a straight figure rather than a range.
About Caenby and its setting
Caenby is a small hamlet situated on the riverside in Lincolnshire, with an elevation of 27 metres above sea level. Caenby lies near the cities of Lincoln and other nearby places such as Glentham and Normanby-by-Spital. Caenby is characterized by its predominantly detached housing stock and is located approximately 11 miles from Lincoln. Caenby is also about 131 miles north of London.
Fuel drain cover around Caenby and across Lincolnshire
Petrol in diesel call-outs in Caenby — part of the LN postcode area — go to vans that likewise cover the places round it, Glentham, Normanby-by-Spital and Owmby-by-Spital among them. The vehicle does not need to move to us: our engineers drain on a forecourt, in a supermarket car park, in a lay-by or on your own driveway.
At the pump around Caenby, still?
No position is better: that is where you now are. Keep it off. Phone.