How Worried Should You Be? Petrol in a Diesel Car in Maesteg
Far less than you probably are, if it hasn't been started. "Have I wrecked it?" is the first question anyone in Maesteg asks, and the truthful answer is normally no, because petrol left in a diesel tank hurts nothing until it is dragged through the fuel system — by ignition priming, by the starter, or by driving. To keep the vehicle that way, call Petrol in Diesel and leave the motor alone. Below, this page sets out what petrol really does inside a diesel, how far it might have got, and how to stop it happening to you a second time.
What petrol in a diesel does to your engine
Diesel has two tasks on its way through a motor. Before it combusts, it lubricates — then it combusts. Extremely fine tolerances go into the fuel injectors and the high-pressure pump, and just your diesel running through stops their surfaces grinding together.
Poorly at the first, not at all at the second: that's petrol. It is runnier than diesel and strips away the lubrication your fuel system depends on, so a pump running on a petrol mix is a pump wearing itself. And petrol is made to resist igniting under compression, which is the opposite of what a diesel needs from its fuel. That's where the knocking comes from.
Put these together and the shape of the trouble is clear. Contact doesn't do the damage — circulation does. Where the petrol is only inside your tank, it is a problem of fuel, nothing more. The start of a mechanical problem is a pump that has been labouring on that petrol — and whatever a worn pump sheds moves on with your fuel to your injectors beyond it.
Petrol in a diesel around Maesteg: how serious is it? Four cases
The best case there can be: filled up, never started. That petrol is inside that tank and just the tank, and the job is a drain and a flush where the vehicle stands. This is the one scenario that can only truly take place at a forecourt, because anywhere else the vehicle has been driven to get there.
A moment's running, or merely your ignition on. Once primed, your system has drawn petrol out of the tank up to the fuel filter and the fuel lines. Drain, flush, see to the filter: still usually straightforward.
Those few miles driven meant your pump working on fuel weakened by petrol throughout. Mileage is only half of that; how hard it was driven matters just as much. Either way this work runs to that tank, the fuel lines, your filter and clean fuel through the whole system. Driving the children to the local primary school is one kind of trip. Getting as far as Swansea, under 15 miles away, makes a very different task — as does any distance on the M4, under 5 miles from Maesteg, with the engine working hard all the way.
Driven until it protested. Clattering, an uneven idle, smoke, a throttle that has gone soft. What you are hearing is the engine reporting fuel that no longer acts like diesel. Pull up where you are — on the verge on Neath Road, at the kerb, down a side road — and don't move it again. The drain and flush still go first, and they deal with it: if a car is pulled over quickly, permanent damage is very uncommon.
Maesteg motorists and that petrol in a diesel stories they hear
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 bigger tank, still the same mixture. That advice presumes a diesel fuel system tolerates petrol by percentage. It doesn't.
Myth: a modern diesel copes with a bit of petrol. If anything, the reverse. A newer diesel runs its fuel through more precise components at higher pressure, which makes the protection count more, not less.
Myth: "If it starts and drives, there's no damage done." This is the one that fools motorists. A petrol motor fed diesel generally won't run, so the motorist stops and the damage stops with them. Nothing seems to have happened when a diesel fed petrol fires up, ticks over and drives away, as it usually will; meanwhile the pump wears. Running does not mean fine.
Myth: "Add some two-stroke oil and drive it home." It's an old fix for a distinct issue. It doesn't put back what petrol has diluted, and that petrol is still inside your tank afterwards.
"Drain it yourself and you are sorted" — a myth, because after it has been running some petrol lies in the filter and lines, waiting to go straight back through the pump on your next start. And, a can of petrol filled at the roadside is truly hazardous.
Petrol in a diesel: how does it occur?
It is rarely carelessness, and no one does it on purpose. A diesel nozzle mostly won't fit a petrol vehicle, yet the smaller petrol nozzle goes into the filler of a diesel almost without resistance — so forecourts make this one mistake simple, and just in that direction.
The moment habit stops matching your car is the moment it happens. Any car that's new to you — hired, on loan as a courtesy car, or brand new. One petrol and one diesel on the drive of the same household. The pumps in a different order on a familiar forecourt. Filling up in a rush on the way to the nearest station, with a train to catch. A new-to-you diesel Volkswagen Golf, its first fuelling, and a driver used to petrol: precisely when it happens. The hand repeats what it has always done when you add rain, a phone call or a back seat full of kids.
Maesteg people: how to avoid petrol in a diesel next time
- Read the petrol pump, not the colour. In the UK unleaded handles are usually green and diesel black, but not on each forecourt. The label is what matters.
- The first fill in a strange motor is the time to check the filler flap — on it, or on the cap, many motors state the fuel to use.
- One of each in the house? Label the key to your diesel — a coloured fob, a sticker — since intending to remember is not enough.
- "Diesel", out loud, before you pick up the nozzle — each time a new or hired car gets its first tank. It seems silly. It works.
- Put your phone away. This is an easy mistake to make while you are thinking about something else.
- Up to a point, a misfuel inhibitor helps: some diesels come with a filler built to refuse a petrol nozzle, and add-on devices are available for the remainder. Treat it as a safety net, and keep checking the petrol pump.
- Less petrol makes a weaker mix, so stop as soon as you notice — while remembering that your next stage is unchanged. It's still not to crank it.
Petrol already in a diesel around Maesteg? Begin here
Then, there is just a short order of things. Do not switch the ignition on, and do not start it. Ask the staff to help you roll it clear of the petrol pump if you're still on the forecourt, whether that's Oils for Wales or anywhere else. What was put in, about how much, and if it's run: tell us that when you phone 0333 366 0103.
If it was AdBlue rather than petrol, say so. That's a different problem — corrosion and deposits rather than lost lubrication — and it has its own page for Maesteg.
What makes one Maesteg petrol in a diesel task cost more than the next
Four different tasks sit behind the four scenarios above — which is why there's no fair single price. What shifts your cost is chiefly which of them you are in. Where the car is matters too, and whether a van can safely reach it, after the proportion of petrol to what your tank holds.
That's why our technicians ask three questions before pricing rather than after: what was put in, how much, and if it has run. A range becomes a straight figure once those answers are in.
About Maesteg, briefly
Maesteg is a town situated in the valley of the River Llynfi in south Wales, with a population of around 9816 people. Maesteg has a mix of housing types, but is predominantly characterised by terraced homes. Maesteg sits at an elevation of 131 metres, near the communities of Y Parc, Llwydarth, and Twmpath-Mawr. Maesteg is located approximately 12 miles from Swansea, the nearest city.
Across Bridgend and in Maesteg: fuel drain cover
Maesteg waits in the CF postcode area, and the vans that answer petrol in diesel calls there work the locations near it as well — Y Parc, Llwydarth and Twmpath-Mawr among them. You need not bring your vehicle to us. Forecourts, supermarket car parks, lay-bys and your own drive are all places where we work.
Maesteg: still at the pump?
Then you are in the best place there can be. Ring, and leave it switched off.