How Worried Should You Be? Petrol in a Diesel Car in Knott End-on-Sea
If it has not been started, worry far less than you probably are. Petrol resting in a diesel tank does nothing to the engine until something draws it through the fuel system — your ignition priming the pump, the starter, or the drive on its own. So the fair answer to the first question anyone around Knott End-on-Sea asks, "have I wrecked it?", is usually no. To keep the car that way, ring Petrol in Diesel and leave the engine alone. Below, you will find what petrol actually does inside a diesel, how far it might have gone, and how to stop it happening to you a second time.
The motor and petrol in a diesel: what goes on
Diesel has two jobs on its way through an engine. Lubricating comes before burning; it does both. Very fine tolerances are built into your injectors and the high-pressure fuel pump, and only your diesel flowing through stops those surfaces grinding together.
Of those two tasks, petrol handles the first poorly and the second not at all. Being less viscous than diesel, petrol strips away the lubrication a fuel system needs, so a pump on the mixture wearing itself. It is equally made to resist igniting under compression — the opposite of what a diesel needs — which is where you hear the knocking.
Put these together and the shape of the issue is clear. It is movement that causes the harm, not contact. Where that petrol is only inside the tank, it's a problem of fuel, nothing more. Whatever a worn pump sheds goes on, carried by your fuel, into your injectors downstream, which is why a pump that has worked on the petrol is where a mechanical problem starts.
Petrol in a diesel in Knott End-on-Sea: how serious is it? Four cases
The best case there can be: filled up, not once started. At a forecourt, and really only there, the petrol is still limited to the tank — since anywhere else the car was driven to reach it. The task is draining and purging on the spot.
Ignition on, or started for a second. With the fuel system primed, your lines and filter now contain petrol that came from the tank. That is usually still an easy task — a drain, a flush, and the filter dealt with.
Some miles driven, and your pump has spent every one of them labouring on diluted fuel. Distance is only half of it; how hard it was driven counts just as much. Either way the work includes that tank, the lines, the fuel filter and fresh fuel through the entire circuit. Driving the children to St. Mary's Catholic Primary School, Fleetwood is one kind of trip. A run as far as Lancaster, under 15 miles away, is a very different job. So is any mileage on the M55, under 10 miles from Knott End-on-Sea, where your engine has been working hard throughout.
It complained, and only then stopped: smoke, clattering, a throttle gone soft, an idle gone uneven. The motor is telling you your fuel is no longer acting like diesel. Whether it's the verge on Lancaster Road, a lay-by or a side road, stop there then leave it. Permanent damage is very uncommon if a vehicle is stopped soon, and the drain and flush that still go first deal with it.
Stories Knott End-on-Sea people hear about petrol in a diesel
"Top it up the rest of the way with diesel and it'll be fine" — a myth. It will not. Nothing is removed by topping up — you are left with a bigger tank, still the same mixture. Percentage isn't how a diesel fuel system copes with petrol, however much that advice supposes.
Myth: "A modern diesel can cope with a bit of petrol." If anything, the reverse. Protection counts more on modern diesels, not less, since their fuel passes through more precise parts at higher pressure.
"It starts, it drives, so there is no harm" — the myth that catches most people than any other. A petrol motor fed diesel normally will not run, so the motorist stops and the damage stops with them. Whilst the pump grinds, a diesel fed petrol normally starts, ticks over and drives away as though nothing has happened. A running engine doesn't mean fine.
Not so: a two-stroke additive makes it safe to drive home. It was an old fix, meant for another problem. None of what petrol thinned is put back by it — and afterwards, the tank still contains that petrol.
"Drain it yourself and you are sorted" — a myth, because after it's been running some petrol sits in your filter and lines, ready to go straight back through the pump on your next start. And, a can of petrol drained by the kerbside is genuinely dangerous.
How petrol ends up: petrol in a diesel
It's rarely carelessness, and nobody does it on purpose. A diesel nozzle mostly will not go into a petrol motor, yet the smaller petrol nozzle goes into the filler of a diesel almost without resistance — so forecourts make this one mistake easy, and just in that direction.
The moment routine stops matching your car is the moment it occurs. 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 hurried fill en route to Poulton-Le-Fylde with a train to catch. A new-to-you diesel Volkswagen Golf, its first fuelling, and a driver used to petrol: precisely when it occurs. The hand repeats what it has always done once you add rain, a phone call or a back seat full of kids.
Knott End-on-Sea motorists: how to avoid petrol in a diesel next time
- Not every forecourt in the UK keeps to green for unleaded and black for diesel, even if most generally do. Check the petrol pump's label; the colour is just a hint.
- Check your filler flap. Plenty of vehicles state the fuel type inside the flap or on the cap. Look at it on your first fill in a car you don't know.
- One of each in the household? Label the key to your diesel — a coloured fob, a sticker — since intending to remember is not enough.
- Say it before you lift it. On the first fill in a new or hired car, say "diesel" aloud before you take the nozzle off the petrol pump. It sounds silly and it does the trick.
- Mistakes like this are simple to make whilst your mind is on something else, so your phone goes away.
- Up to a point, a misfuel inhibitor helps: some diesels have a filler built to block a petrol nozzle, and aftermarket devices are available for the rest. Treat it as a backstop, then keep reading the pump.
- As soon as you realise, stop: less petrol in that tank means a thinner mix. What to do next does not change, though — still don't fire it up.
Petrol already in a diesel around Knott End-on-Sea? Begin here
Short and simple, then, is the order of things. Don't fire it up, and don't switch your ignition on. Still at the forecourt, at Asda or anywhere else? Ask the staff to help you roll it away from the petrol pump. Then call 0333 366 0103 and tell us what went in, about how much, and if it's run.
Say so if it was AdBlue rather than petrol: it's a different fault, with its own page for Knott End-on-Sea, because AdBlue brings corrosion and deposits instead of lost protection.
One petrol in a diesel task around Knott End-on-Sea costs more than another. Why?
There's no honest single price for this, because the four situations above are four different jobs. Mostly, your cost moves with which situation you're in. Where the vehicle is matters too, and whether our van can safely get to it, after the share of petrol to what that tank takes.
Three queries come first, before any quote, instead of after — what was put in, how much, has it run — and this is the reason. A range becomes a straight figure when the replies are in.
About Knott End-on-Sea itself
Knott End-on-Sea is a small coastal village in Lancashire, situated on the north shore of the River Wyre estuary. Knott End-on-Sea has a low elevation of around 9 metres above sea level and is located near the villages of Pilling Lane and Preesall. Knott End-on-Sea remains a quiet residential community with a mix of housing types, predominantly semi-detached homes.
Fuel drain cover across Lancashire, Knott End-on-Sea included
Our teams answering petrol in diesel jobs in Knott End-on-Sea, in the FY postcode area, equally work the spots around it, Pilling Lane, Preesall and Marsh Side Farm included. A forecourt, a supermarket car park, a lay-by or your own drive are all places our technicians work, and the car doesn't need to come to us.
Knott End-on-Sea: still at the petrol pump?
Then you are in the best place there can be. Switched off it stays; then phone.