Should You Worry? Petrol in a Diesel Car in Walkford
If it has not been started, worry less than you probably are. Till the ignition primes your pump, your starter cranks, or your vehicle is driven, petrol in a diesel tank just waits there and does nothing. Which means the honest reply to the first Walkford query — "have I ruined it?" — usually no. To leave it that way, ring Petrol in Diesel and leave the engine alone. The rest of this page sets out what petrol really does to a diesel, how to tell 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 your engine?
On its way through a motor, diesel has two tasks. Before it ignites, it lubricates — then it ignites. What keeps the surfaces inside your high-pressure pump and the fuel injectors from wearing down against one another is the diesel passing through them — they're made to extremely fine gaps.
Of those two jobs, petrol manages the first badly and the second never. Being less viscous than diesel, petrol strips out the protection a fuel system needs, leaving a pump running on the mixture wearing itself. It is equally made to resist igniting under compression — the opposite of what a diesel needs — which is why you hear the knocking.
The shape of the problem is clear when you put those together. Not contact but circulation is what causes the harm. Petrol in a tank is a fuel problem. Once the pump has been working on that petrol, a mechanical problem has begun: anything shed by a pump that's grinding is carried onward to the injectors with your fuel.
Walkford, petrol in a diesel: four situations, from mild to serious
Fuelled up, not once started. The best case there is. That petrol is in that tank and only that tank, and the job is a drain and a flush where your car stands. This is the one situation that can only really occur on a forecourt, because anywhere else the vehicle has been driven to get there.
Your ignition turned on, or a brief start. With the fuel system primed, the lines and filter now contain petrol that has come from your tank. Drain, flush, deal with the filter: still usually simple.
Those few miles driven meant the pump running on fuel diluted by petrol throughout. Miles is only half of that; how hard it was driven matters just as much. Either way this work runs to your tank, your lines, the filter and clean fuel through the entire system. Driving the kids to Highcliffe St Mark Primary School is one sort of trip. Driving as far as Southampton, under 25 miles away, makes a very different task — as does any miles on the M27, under 15 miles from Walkford, with your engine running hard all the way.
Driven on till it complained — rattling, smoke, a ragged idle, a dead throttle. What you are hearing is the engine signalling fuel that no longer behaves like diesel. Stop where you are — on the verge on Ringwood Road, at the kerb, down a side road — and don't move it again. A car pulled over early very seldom has lasting damage, since the fuel drain and the flush, which still go first, sort it out.
What Walkford motorists get told about petrol in a diesel — and the stories in it
"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're left with a bigger tank, still the same mixture. That advice assumes a diesel fuel system handles petrol by percentage. It does not.
If anything, the reverse is true. Myth: "A modern diesel can cope with a bit of petrol." A newer diesel sends its fuel through smaller parts at higher pressure, which makes the lubrication matter more, not less.
"It starts, it drives, so there is no harm" — the myth that catches most people than any other. The driver of a petrol engine fed diesel usually stops, since it will not run, and the damage stops with them. A diesel fed petrol generally starts, ticks over and drives away as though nothing has happened, while the pump wears. Being able to run isn't the same as being fine.
"A drop of two-stroke oil and drive it home" — a myth, borrowed from a fix from years ago, for a distinct fault. The petrol is still inside that tank after that, and what it has diluted isn't put back.
If the engine has run, part of that petrol sits in the fuel filter and the fuel lines, not your tank — and your next start pulls it right back through your pump. So the myth "drain your tank yourself and you're sorted" does not hold. It is also genuinely dangerous to drain petrol into a can by the kerbside.
How does petrol in a diesel take place?
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, while the diesel one mostly will not fit a petrol motor. That's how the forecourt makes it simple.
It occurs when habit and your car stop matching. Any motor that is new to you — a hire car, on loan as a courtesy car, or brand new. A household with one petrol and one diesel on the driveway. A well-known forecourt with the pumps in a different order. Racing for a train outside Hinton Admiral and filling up en route. Years of petrol cars behind you, a diesel Renault Megane in front of you on the forecourt for its first tank — that's when. With rain, a call coming in, or children to deal with, your hand just does what it always has.
How to avoid petrol in a diesel at your next fill-up in Walkford
- Not every forecourt in the UK keeps to green for unleaded and black for diesel, even if most usually do. Read the petrol pump's label; the colour is only a hint.
- In a car you don't know, look inside the flap over the filler or at the cap before the first fill: many vehicles state the fuel there.
- Mark your key. In a home with one of each, a coloured fob or a sticker on your diesel's key does more than any amount of intending to remember.
- "Diesel", out loud, before you lift the nozzle — each time a new or hired car gets its first tank. It seems daft. It does the trick.
- Mistakes like this are easy to make while your mind is on something else, so your phone goes away.
- Some diesels come with a filler built to reject a petrol nozzle, and devices you can add exist for vehicles without one. Such an inhibitor helps up to a point — as a backstop, not a reason to stop checking the petrol pump.
- The moment you notice, stop: less petrol inside your tank means a thinner mixture. What to do next doesn't change, though — still do not start it.
Put petrol in a diesel around Walkford already?
The order of things is short, then. Starting it is out, and so is turning on your ignition. The staff on the forecourt — whether at Esso itself or wherever you filled up — will usually help push it clear of the pump if you ask. What went in, roughly how much, and if it's run: tell us those when you call 0333 366 0103.
If it was AdBlue rather than petrol, say so. That is a separate fault — corrosion and deposits and not lost lubrication — and it has its own page for Walkford.
Why one petrol in a diesel task around Walkford costs more than another
The four scenarios above are four separate tasks, so no single price for this would be fair. Which of them you are in is chiefly what moves your cost. After that it is the proportion — how much petrol was put in against how much that tank takes — and then where your car is and whether our van can get to it safely.
That's why we ask three questions before quoting instead of after: what was put in, how much, and if it's run. A range turns into a straight figure when those replies are in.
About Walkford itself
Walkford is a suburban area in Dorset, situated near the coast and approximately 37 metres above sea level. Walkford lies close to the nearby places of Hinton, Highcliffe, and Beckley, and is characterised by its predominantly detached housing stock. Walkford is located near the city of Southampton, which is around 16.6 miles away, and is also within commuting distance of London, at around 85.7 miles away.
Across Dorset and around Walkford: fuel drain cover
Petrol in diesel jobs in Walkford — part of the BH postcode area — go to vans that likewise cover the spots around it, Hinton, Highcliffe and Beckley included. The vehicle does not need to move to us: we drain on a forecourt, in a supermarket car park, in a lay-by or on your own driveway.
Walkford: still at the pump?
In that case, you could not be in a better position. Switched off it stays; then phone.