Petrol in a Diesel Car in Gartcosh: How Worried Should You Be?
If it hasn't been started, worry far less than you probably are. Until your ignition primes your pump, the starter turns, or your car is driven, petrol in a diesel tank just rests there and does nothing. Which makes the truthful reply to the first Gartcosh query — "have I ruined it?" — normally no. Petrol in Diesel is who to phone, with the engine left off, and so it stays that way. Further down, this page sets out what petrol really does inside a diesel, how far it might have gone, and how to stop it happening to you a second time.
What petrol in a diesel does to the motor
On its way through an engine, diesel does two tasks. It ignites, and before it burns it protects. What stops the surfaces inside your high-pressure pump and the injectors from wearing against one another is the diesel flowing through them — they're designed to extremely fine clearances.
Badly 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 rests on, and so a pump running on a petrol mixture 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 rattling comes from.
Put those together and the shape of the issue is plain. The harm is done by movement, not by contact. All a tank with petrol in it amounts to is a fuel problem. Whatever a worn pump sheds travels on, carried by your fuel, into the fuel injectors downstream, which is why a pump that has worked on the petrol is where a mechanical issue begins.
How serious is petrol in a diesel? Four situations our engineers see in Gartcosh
The best case there can be: filled up, not once started. At a forecourt, and really only there, the petrol is still limited to that tank — because everywhere else your car was driven to get to it. The task is emptying and cleaning on the spot.
A brief spell of running, or merely the ignition on. Petrol has left your tank and reached your filter and the lines, because the system has been primed. Normally little more than emptying, purging and seeing to your filter, so still simple.
Those few miles driven were your pump running on fuel weakened by petrol throughout. Tank, lines, filter, then clean fuel put through the entire circuit: that's this work, and the way the vehicle was driven matters as much as the mileage. Driving the kids to the local primary school is one sort of trip. A run as far as Glasgow, under 10 miles away, is a very different job. So is any mileage on the M73, under a mile from Gartcosh, where the motor has been running hard throughout.
Driven on till it complained — knocking, smoke, a lumpy idle, a soft throttle. That's your engine telling you its fuel has stopped behaving like diesel. Stop where you are — on the verge on Kirkhill Road, at the kerb, down a side road — and don't move it. Permanent damage is very unusual when a car is stopped soon, and the fuel drain and flush-through that still go first deal with it.
Petrol in a diesel stories Gartcosh motorists hear
False: topping up to full with diesel makes it fine. It doesn't. Topping up takes out nothing; it gives you a fuller tank of the same mixture. Percentage isn't how a diesel fuel system tolerates petrol, whatever that guidance presumes.
If anything, the reverse is true. Myth: "A newer diesel can cope with a bit of petrol." Finer parts and higher pressure are how a modern diesel runs its fuel, and that makes the protection matter more, not less.
"It starts, it drives, and so no harm done" — the myth that catches most drivers than any other. Diesel in a petrol motor normally leaves a motor that won't run: the driver stops, and so does the harm. A diesel fed petrol generally starts, ticks over and drives away as if nothing has happened, while the pump grinds. Running isn't the same as fine.
"A drop of two-stroke oil and drive it home" — a myth, taken from a fix from years ago, for a separate fault. It does not put back what petrol has thinned, and that petrol is still inside the tank later.
The next start sends petrol back round your pump out of your lines and the fuel filter, where some of it sits after the motor has been run. That's why draining your tank yourself doesn't sort it — a myth. And, a can of petrol filled at the roadside is genuinely hazardous.
How does petrol in a diesel occur?
It's rarely carelessness, and no one does it on purpose. The petrol nozzle is the slimmer of the two and slides into a diesel filler with almost no resistance; a diesel nozzle mostly won't go into a petrol motor at all. The forecourt makes it simple, and the slip runs one way.
The moment routine stops matching the car is the moment it takes place. Hire cars, courtesy cars, and vehicles that are new to you. Households running one of each, petrol and diesel. Your normal forecourt, its pumps suddenly in a different order. Rushing for a train outside the nearest station and filling up en route. Precisely the moment it occurs: after years of driving petrol, someone fills a diesel Volkswagen Passat for the first time. Throw in a back seat full of children, a phone call or rain, and the hand takes over.
Next time you fill up around Gartcosh: preventing petrol in a diesel
- Check the pump, not the colour. In the UK unleaded handles are normally green and diesel black, yet not on every forecourt. The label is what matters.
- Inspect 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 vehicle you don't know.
- Mark the key. In a home with one of each, a coloured fob or a sticker on the diesel's key does more than any amount of intending to remember.
- Before the nozzle comes off the pump the first time you fuel a hired or new motor, say "diesel" out loud. Silly, yes, yet it works.
- Thinking about something else is when this becomes an easy mistake to make, and so put your phone away then keep your mind on the pump.
- Some diesels come with a filler built to block a petrol nozzle, and devices you can add exist for motors without one. Such an inhibitor helps up to a point — as a safety net, not a reason to stop reading the petrol pump.
- Spotting it mid-fill? Stop at once. A thinner mix results from less petrol in your tank, but your next step remains the same: do not fire it up.
Put petrol in a diesel around Gartcosh already?
Then, there is just a short order of things. Starting it is out, and so is turning on the ignition. If you are still at the forecourt — BP or anywhere else — ask the staff to help you push it away from the pump. Ring 0333 366 0103 next, with three facts — your fuel, the approximate amount, and if it's run.
Corrosion and deposits form the problem with AdBlue, whereas petrol brings lost protection. So if it was AdBlue, say so — and read its own Gartcosh page.
Why one petrol in a diesel task around Gartcosh costs more than another
A fair single quote doesn't exist here: four scenarios, four separate tasks. What moves your cost is mostly which of them you are in. Next it's the proportion — how much petrol got in against how much the tank holds — and then where the car is and whether a technician can get to it safely.
That's why we ask three queries before costing instead of after: what went in, how much, and if it's run. The answers turn a range into a straight figure.
About Gartcosh
Gartcosh is a village in North Lanarkshire, situated on the shores of Gartloch lake at an elevation of 87 metres. Gartcosh lies close to the cities of Glasgow and the surrounding towns of Marnock and Muirhead. Gartcosh has a population of around 1668 people, predominantly living in detached housing. Gartcosh is located approximately 6 miles from Glasgow city centre.
Across North Lanarkshire and around Gartcosh: fuel drain cover
Marnock, Muirhead and Gartloch are among the places near Gartcosh that the same vans work, answering petrol in diesel calls across Gartcosh's G postcode area. Our technicians drain where your vehicle is — your own driveway, a lay-by, a supermarket car park, a forecourt — so it does not have to come to us.
Gartcosh: still at the pump?
The best spot there is, then — that's where you are. Leave the car switched off, then ring.