Should You Worry? Petrol in a Diesel Car in Maguiresbridge
Far less than you likely are, provided it has not been started. "Have I ruined it?" is the first thing anyone in Maguiresbridge asks, and the honest answer is normally no, because petrol resting in a diesel tank harms nothing till it's drawn through the fuel system — by ignition priming, by the starter, or by driving. Petrol in Diesel is who to call, with the engine left off, and so it stays that way. The remainder of this page covers what petrol actually does to a diesel, how to judge how far it has got, and how to make sure it doesn't happen to you again.
Inside the motor: what petrol in a diesel does
Two tasks fall to diesel on its journey through a motor. Oiling comes before burning; it does both. Made to extremely fine clearances, the fuel injectors and your pump rely on your diesel flowing through them to keep their surfaces from wearing against one another.
Of those two jobs, petrol handles the first poorly and the second never. It's thinner than diesel and strips away the protection the fuel system depends on, and so a pump running on a petrol mixture is a pump wearing itself. And petrol is designed to resist igniting under compression, which is the opposite of what a diesel needs from its fuel. That's where the clattering comes from.
Taken together, they make clear the shape the issue has. It is movement that causes the harm, not contact. All a tank with petrol in it amounts to is a fuel issue. After the pump has been running on that petrol, a mechanical fault has started: whatever is shed by a pump that's wearing is carried onward to the fuel injectors with your fuel.
How bad is petrol in a diesel? Four situations we see around Maguiresbridge
Filled but not once started — the best it gets. Being on a forecourt is what makes this possible: elsewhere, your car has been driven there to begin with. With the petrol held inside that tank alone, it's emptied and cleaned right where it stands, and nothing more is needed.
A moment's running, or merely the ignition on. Petrol has come out of the tank and reached your filter and your lines, because your system has been bled. Drain, flush, deal with your filter: still usually easy.
Some miles driven, and your pump has spent every one of them running on weakened fuel. The work is your tank, the fuel lines, your filter and fresh fuel through the whole circuit, and how hard your car was driven counts as much as how far. A school run to the local primary school is one thing. Getting as far as Armagh, under 50 miles away, makes a very different job — as does any miles on the M77, over 50 miles from Maguiresbridge, with the motor working hard the whole time.
Driven until it complained. Knocking, a lumpy idle, smoke, a throttle that has gone soft. What you are hearing is the engine reporting fuel that no longer runs like diesel. Pull up wherever you are — the verge on Wallace Cottages, a lay-by, a side street — then leave it where it is. Permanent damage is very uncommon if a vehicle is stopped quickly, and the drain and flush-through that still go first deal with it.
What Maguiresbridge drivers get told about petrol in a diesel — and the stories in it
Myth: "Fill it the rest of the way with diesel and it will be fine." It will not. A fuller tank of the same mixture is all you get, because topping up takes out nothing. The assumption behind that advice — that diesel fuel systems accept petrol by percentage — is wrong.
"Current diesels can handle a little petrol" — a myth, and closer to the reverse. Finer parts and higher pressure are how a modern diesel runs its fuel, and that makes the lubrication matter more, not less.
This is the one that fools people. Myth: "If it starts and drives, there's no damage done." The driver of a petrol motor fed diesel normally stops, because it will not run, and the harm stops with them. Whilst your pump grinds, a diesel fed petrol normally starts, ticks over and drives away as though nothing has happened. Running does not mean fine.
Myth: "Add some two-stroke oil and drive the vehicle home." It is an old workaround for a separate problem. What petrol has thinned remains weakened, and the petrol remains inside that tank anyway.
Myth: "Drain your tank yourself and you're sorted." Once the engine has been run, some of that petrol is no longer in your tank: it is in the filter and the lines, and it goes right back through the pump at your next start. On top of that, petrol cleared into a can by the road is genuinely risky.
Petrol in a diesel: how does it occur?
Carelessness is rarely the cause, and nobody means to do it. One way only, because of the nozzles: the slimmer petrol one slides inside a diesel filler with almost no resistance, whereas the diesel one generally won't fit a petrol vehicle. That is how the forecourt makes it simple.
It occurs when routine and your car stop matching. Courtesy car, hire car, or a car that's new. Two vehicles on one driveway, one petrol, one diesel. A forecourt you know, but with its pumps laid out differently. Filling up in a hurry on the way to the nearest station, with a train to catch. The first fill-up in a diesel Volkswagen Passat after years of driving petrol is exactly the moment it occurs. Throw in a back seat full of children, a phone call or rain, and the hand takes over.
Next time you fill up around Maguiresbridge: avoiding petrol in a diesel
- Green for unleaded and black for diesel is normal in the UK — yet not on each forecourt. Trust the label on the pump, not the colour.
- Check your filler flap. Plenty of motors state the fuel type inside the flap or on the cap. Look at it on the first fill in any car you don't know.
- Mark your key. In a household with one of each, a coloured fob or a sticker on the diesel's key does more than any amount of meaning to remember.
- It seems silly and it works: on the first fill in a new or hired car, say "diesel" out loud before you lift the nozzle off the pump.
- Mistakes like this are simple to make whilst your mind is on something else, and so the phone goes away.
- Add-on devices are available for motors without one, and some diesels are built with a filler that won't accept a petrol nozzle. Useful — but a safety net at best, never a reason to stop checking the label.
- Spotting it halfway? Stop at once. A weaker mix follows from less petrol in your tank, yet your next step stays the same: do not fire it up.
Put petrol in a diesel around Maguiresbridge already?
Then, there is only a short order of things. Starting it is out, and so is turning on the ignition. The attendants on the forecourt — whether at the nearest petrol station itself or wherever you filled up — will normally help push it clear of the petrol pump if you ask. Then ring 0333 366 0103 and tell us what went in, roughly how much, and if it has run.
Say so if it was AdBlue instead of petrol: it is a different problem, with its own page for Maguiresbridge, because AdBlue brings corrosion and deposits instead of lost protection.
One petrol in a diesel job in Maguiresbridge costs more than another. Why?
A fair single price does not exist here: four scenarios, four separate tasks. What shifts the cost is chiefly which of them you are in. Where the car is counts too, and whether a van can safely get to it, after the proportion of petrol to what that tank takes.
Before any quote, not after, we ask three questions: your fuel that went in, the quantity, and whether it's run. That's why. A range becomes a straight figure once those replies are in.
About Maguiresbridge and its setting
Maguiresbridge is a small locality in County Fermanagh, situated inland at an elevation of 53 metres. Maguiresbridge lies near several other settlements, including Brookeborough, Lisnaskea, and Lisbellaw, and is approximately 32.9 miles from the city of Armagh. Maguiresbridge has a population of around 940 people, predominantly living in semi-detached housing. Maguiresbridge is located in a rural area, some 361.1 miles from London.
Across County Fermanagh and in Maguiresbridge: fuel drain cover
Maguiresbridge waits in the BT postcode area, and our teams that answer petrol in diesel jobs there work the locations near it as well — Brookeborough, Lisnaskea and Lisbellaw among them. No need to move your car to us. Forecourts, supermarket car parks, lay-bys and your own driveway are all spots we drain.
Maguiresbridge: still at the pump?
No position is better: that's where you now are. Keep it off. Phone.