Should You Worry? Petrol in a Diesel Car in Colwinston
Provided it hasn't been started, worry less than you likely are. Everyone around Colwinston starts with "have I ruined it?", and the honest answer is usually no: petrol left inside the tank of a diesel remains harmless until priming, cranking or driving pulls it into your fuel system. To keep the car like that, call Petrol in Diesel and leave your motor alone. What petrol really does to a diesel, how to judge how far it has gone, and how to stop it from happening again: that's the rest of this page.
Inside your engine: what petrol in a diesel does
Two tasks fall to diesel on its journey through a motor. It combusts, and before it burns it protects. The high-pressure pump and your injectors are made to very fine gaps, and your diesel passing through them is what keeps those surfaces from wearing against one another.
Poorly at the first, not at all at the second: that is petrol. The rattling comes from petrol being designed not to ignite when compressed, which is precisely the reverse of what a diesel needs. On top of that it is runnier than diesel, it strips out the protection your system hinges on, and any pump working on such a mixture is wearing itself.
Put those together and the shape of the issue is clear. The damage is done by circulation, not by contact. Petrol in a tank is a fuel problem. A pump that has been working on that petrol is the start of a mechanical one, and whatever a worn pump sheds moves on with the fuel to the fuel injectors downstream.
Petrol in a diesel around Colwinston: how bad is it? Four situations
Filled up, and not started: nothing beats it. Being at a forecourt is what makes this possible: elsewhere, your car has been driven there to begin with. With that petrol kept inside the tank alone, it's drained and flushed right where it stands, and nothing more is needed.
A moment's running, or just the ignition on. The system has been primed, and so petrol has left that tank and reached your filter and the fuel lines. That's usually still an easy job — a drain, a flush, and your filter seen to.
A few miles driven, and your pump has spent each of them working on thinned fuel. How hard the vehicle was driven matters as much as how far, and this work takes in that tank, your lines, your filter and clean fuel through the entire circuit. On the school run to the local primary school, the distance is short. Very different a second time: a run to Cardiff, under 25 miles away, or some miles on the M4, under 5 miles from Colwinston, where your engine never stopped working hard.
It protested, and only then stopped: smoke, clattering, a throttle gone soft, an idle gone uneven. What you are hearing is the motor reporting fuel that no longer behaves like diesel. Leave it wherever it stops: a lay-by, a side street, the verge on Beech Park. Long-term damage is very unusual if a car is stopped quickly, and the drain and flush-through that still go first take care of it.
Petrol in a diesel stories Colwinston motorists hear
It will not be fine. The myth: "Fill it the rest of the way with diesel and it will be." Topping up takes out nothing; it gives you a bigger tank of the same mix. A diesel fuel system does not tolerate petrol by percentage in the way that guidance presumes.
If anything, the opposite is true. Myth: "A newer diesel can cope with a bit of petrol." At higher pressure, through finer components: that's how a modern diesel moves its fuel, and so the protection matters more, not less.
The myth that catches people out: if it starts and drives, it must be unharmed. Feed diesel to a petrol motor and it generally won't run, so the motorist stops — and the damage stops with them. Nothing looks to have happened when a diesel fed petrol fires up, ticks over and drives away, as it usually will; meanwhile your pump grinds. A running engine doesn't mean fine.
"A drop of two-stroke oil and drive it home" — a myth, borrowed from a fix from years ago, for a different issue. The petrol is still inside the tank after that, and whatever it has diluted is not put back.
"Drain it yourself and you're sorted" — a myth, since after it has been running some petrol sits in the fuel filter and lines, waiting to go straight back through your pump at your next start. Clearing petrol into a can at the kerbside is also really hazardous.
How it happens: petrol in a diesel
No one does it on purpose, and it is seldom carelessness. One way only, because of the nozzles: the narrower petrol one slides inside a diesel filler with almost no resistance, while the diesel one mostly won't fit a petrol motor. That's how the forecourt makes it easy.
It occurs when habit and the car stop matching. Hire cars, courtesy cars, and motors that are new to you. One petrol and one diesel on the drive of the same household. A forecourt you know, but with its pumps arranged differently. Rushing for a train at Bridgend and filling up en route. The first fill-up in a diesel Volkswagen Passat after years of driving petrol is precisely the moment it happens. Your hand repeats what it has always done when you add rain, a phone call or a back seat full of children.
Next time you fill up in Colwinston: avoiding petrol in a diesel
- Read the petrol pump, not the colour. In the UK unleaded handles are normally green and diesel black, but not on every forecourt. The label is what matters.
- Inspect your filler flap. Plenty of vehicles state the fuel inside the flap or on the cap. Look at it on your first fill in a motor you do not know.
- One of each in the house? Mark the key to your diesel — a coloured fob, a sticker — because intending to remember isn't enough.
- "Diesel", aloud, before you lift the nozzle — every time a new or hired car needs its first tank. It sounds silly. It works.
- While you are thinking about something else, this is an easy mistake to make — so tuck the phone away.
- Up to a point, a misfuel inhibitor helps: some diesels come with a filler designed to refuse a petrol nozzle, and aftermarket devices are available for the rest. Count it as a backstop, and keep reading the petrol pump.
- As soon as you notice, stop: less petrol in the tank makes a thinner mixture. What to do next doesn't change, though — still don't start the car.
Colwinston: already put petrol in a diesel?
The order of things is short, then. Leave it unstarted, with your ignition switched off as well. Yet on the forecourt, at the nearest petrol station or anywhere else? Ask the staff to help you push the vehicle away from the pump. Phone 0333 366 0103 next, with three facts — your fuel, the approximate volume, and whether it has run.
If it was AdBlue and not petrol, say so. That's a separate fault — corrosion and deposits instead of lost lubrication — and it has its own page for Colwinston.
One petrol in a diesel task around Colwinston costs more than another. Why?
Four separate tasks lie behind the four situations above — which is why there is no fair single quote. Mostly, the cost moves with which one you're in. Next it is the ratio — how much petrol was put in against how much your tank takes — and then where the car is and whether a technician can get to it safely.
Ahead of any quote, not after, we ask three questions: the fuel that went in, its quantity, and whether it's run. That's why. Given those replies, you get a straight figure instead of a range.
About Colwinston
Colwinston is a small village in the Vale of Glamorgan, situated near the riverside at an elevation of 72 metres. Colwinston lies close to the nearby villages of Llampha, Llangan, and Llandow, and is approximately 15 miles from Cardiff. Colwinston has a population of around 619 people, predominantly living in detached housing. Colwinston is also within commuting distance of major cities, with London being around 146 miles away.
Fuel drain cover across The Vale of Glamorgan, Colwinston included
Llampha, Llangan and Llandow are among the places near Colwinston that the same vans work, answering petrol in diesel call-outs across Colwinston's CF postcode area. The car does not need to come to us: our engineers drain at a forecourt, in a supermarket car park, in a lay-by or on your own drive.
Colwinston: still at the pump?
The best place there is, then — that's where you are. Phone, and leave it turned off.