Should You Worry? Petrol in a Diesel Car in Park Close
If it has not been started, worry less than you probably are. "Have I wrecked it?" is the first question anyone in Park Close asks, and the honest answer is generally no, since petrol left in a diesel tank hurts nothing until it's drawn through your fuel system — by ignition priming, by your starter, or by driving. Petrol in Diesel is who to call, with the motor kept off, so it stays that way. What petrol actually does to a diesel, how to judge how far it has gone, and how to keep it from happening a second time: that's the remainder of this page.
Inside the engine: what petrol in a diesel does
On its way through an engine, diesel has two tasks. Lubricating comes before burning; it does both. Your high-pressure pump and the fuel injectors are built to very fine tolerances, and your diesel passing through them is what stops those surfaces from wearing against one another.
The second task petrol does not do at all, and the first it does poorly. The knocking comes from petrol being made 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 hinges on, and any pump running on that mixture is wearing itself.
The shape of the problem is plain when you put those together. Not contact but movement is what causes the harm. Any tank with petrol in it is a fuel fault. Once your pump has been running on that petrol, a mechanical problem has started: anything shed by a pump that is grinding is carried downstream to your injectors with the fuel.
Four scenarios our engineers see in Park Close: how serious is petrol in a diesel?
The best case there is: filled up, never started. On a forecourt, and really only there, that petrol is still confined to the tank — since anywhere else your car was driven to get to it. The job is emptying and purging on the spot.
A moment's running, or just the ignition on. Once primed, your system has drawn petrol from your tank as far as your filter and the lines. Still usually simple: drain, flush, and the fuel filter seen to.
Your pump now worked a couple of miles on diluted fuel — that is what driving the vehicle meant. The work is that tank, your lines, your filter and fresh fuel through the whole circuit, and how hard the car was driven matters as much as how far. Short trips, such as the school run to Salterforth Primary School, are one thing. Very different once more: a run to Bradford, under 25 miles away, or any mileage on the M65, under 3 miles from Park Close, where your engine never stopped labouring hard.
It protested, and only then stopped: smoke, knocking, a throttle gone soft, an idle gone ragged. The motor is telling you your fuel is no longer acting like diesel. Pull up where you are — on the verge on High Lane, at the kerb, down a side road — and don't move it again. The drain and flush still come first, and they deal with it: if a car is stopped quickly, permanent damage is very uncommon.
What Park Close drivers get told about petrol in a diesel — and the stories in it
It will not be fine. The myth: "Fill it the rest of the way with diesel and it'll be." Nothing is removed by topping up — you're left with a fuller tank, still the same mixture. The idea behind the guidance — that diesel fuel systems accept petrol by percentage — is wrong.
Myth: "A modern diesel can cope with a bit of petrol." If anything, the opposite. More precise components and higher pressure are the way a modern diesel runs its fuel, and that makes the lubrication matter more, not less.
Myth: "If it starts and drives, there is no harm done." This is the one that catches drivers. Diesel in a petrol motor generally means a motor that won't run: the motorist stops, and so does the damage. Nothing looks to have happened when a diesel fed petrol fires up, ticks over and drives away, which it usually will; meanwhile the pump wears. Fine and running are not the same at all.
"A drop of two-stroke oil and drive it home" — a myth, taken from a fix from years ago, for a separate issue. It doesn't put back what petrol has weakened, and that petrol is still in that tank after that.
Myth: "Drain your tank yourself and you're sorted." After the motor has been run, some of the petrol is no longer in your tank: it's in your filter and the lines, and it goes straight back through your pump on your next start. And, a can of petrol filled at the roadside is genuinely dangerous.
How does petrol in a diesel take place?
A careless moment is seldom the cause, and no one means to do it. 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, whilst a diesel nozzle generally will not go into a petrol car at all. So the error runs one way.
Routine and the vehicle getting out of step is how it occurs. Any vehicle that is new to you — a hire car, on loan as a courtesy car, or just bought. A household with one petrol and one diesel on the driveway. The pumps in a different order on a well-known forecourt. Rushing for a train at Colne and filling up en route. Exactly the moment it happens: after years of driving petrol, someone fills a diesel Volkswagen Golf for the first time. Throw in a back seat full of kids, a phone call or rain, and the hand takes over.
How to prevent petrol in a diesel at your next fill-up in Park Close
- Not every forecourt in the UK keeps to green for unleaded and black for diesel, though most generally do. Check the pump's label; the colour is only a hint.
- Plenty of vehicles state the fuel inside the filler flap or on the cap, so check it on your first fill in a car you do not know.
- A coloured fob or a sticker on your diesel's key achieves more than any amount of intending to remember, for a house with one of each.
- It sounds silly and it does the trick: on your first fill in a new or hired car, say "diesel" out loud before you lift the nozzle off the petrol pump.
- Mistakes like this are straightforward to make whilst your mind is on something else, and so the phone goes away.
- A misfuel inhibitor helps, up to a point. Some diesels have a filler designed to refuse a petrol nozzle, and add-on devices are available for cars without one. They are a safety net, not a reason to stop reading the petrol pump.
- As soon as you notice, stop: less petrol in the tank makes a weaker blend. What to do next doesn't change, though — still don't start the vehicle.
Put petrol in a diesel around Park Close already?
Then, there is just a short order of things. Never fire it up, and do not switch the ignition on. Yet on the forecourt, at Total or anywhere else? Ask the staff to help you push the vehicle away from the pump. What went in, about how much, and if it's run: tell us those when you phone 0333 366 0103.
Corrosion and deposits form the trouble with AdBlue, where petrol brings lost lubrication. So if it was AdBlue, say so — and see its own Park Close page.
Why one petrol in a diesel job in Park Close costs more than another
There's no fair single price for this, since the four situations above are four separate tasks. Mostly, your cost shifts with which one you're in. Beyond that it's the share — how much petrol went in against how much the tank holds — and then where the car is and whether our van can reach it safely.
Ahead of any quote, not after, come three queries: the fuel that went in, the quantity, and whether it has run. That's why. Given those replies, there is a straight figure rather than a range.
About Park Close
Park Close is a locality in Lancashire, situated on the riverside in the North West of England. Park Close has a population of around 546 people and is characterized by predominantly detached housing. Park Close is located near other small places such as Salterforth, Hey, and Kelbrook, and is approximately 18.7 miles from the city of Bradford. Park Close sits at an elevation of 182 metres, relatively close to the regional urban centres.
Park Close and Lancashire: where our fuel drain cover runs
Park Close sits in the BB postcode area, and our vans that answer petrol in diesel calls there work the locations near it as well — Salterforth, Hey and Kelbrook among them. We drain where the vehicle is — your own drive, a lay-by, a supermarket car park, a forecourt — so it never needs to come to us.
Still at the petrol pump in Park Close?
No position is better: that's where you now are. Keep it turned off, then ring.