How Worried Should You Be? Petrol in a Diesel Car in Bridgend
Provided it hasn't been started, you can worry less than you probably are. Petrol resting in a diesel tank does nothing to the motor until something draws it through the system — the ignition priming the pump, the starter, or the drive itself. So the truthful answer to the first query everyone in Bridgend asks, "have I wrecked it?", is generally no. Keep it that way: leave your engine off and ring Petrol in Diesel. Below, this page sets out what petrol really does inside a diesel, how far it may have gone, and how to stop it happening to you again.
Petrol in a diesel: what does it do to the motor?
Passing through an engine, diesel is doing two jobs at once. It combusts, and before it burns it lubricates. Designed to extremely fine clearances, your injectors and your pump rely on the diesel moving through them to stop their surfaces wearing against one another.
Of these two tasks, petrol manages the first poorly and the second not at all. A pump running on a petrol mixture is wearing itself out, since petrol is thinner than diesel and strips out the protection your fuel system relies on. Petrol is also designed to resist igniting under compression — the reverse of what a diesel needs from its fuel — and that is where the clattering starts.
Put these together and the shape of the issue is plain. The harm is done by circulation, not by contact. Any tank with petrol in it is a fuel issue. 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 your fuel to the fuel injectors further on.
Petrol in a diesel around Bridgend: how bad is it? Four situations
Filled up, never started. The best case there can be. Being at a forecourt is what makes this the case: elsewhere, the car has been driven there to begin with. With the petrol kept in the tank alone, it's emptied and cleaned on the spot, and nothing more is needed.
Ignition on, or started for a second. The fuel system has been bled, so petrol has left the tank and reached the fuel filter and the lines. Usually little more than draining, rinsing and sorting the filter, and so still simple.
Driven a few miles. Now the pump has spent these miles labouring on thinned fuel. Tank, lines, filter, then fresh fuel run through the entire system: that's the work, and the way the vehicle was driven counts as much as the mileage. On the school run to the local primary school, the mileage is short. Getting as far as Dundee, under 15 miles away, makes a very different task — as does any mileage on the M90, under 25 miles from Bridgend, with your engine working hard the whole time.
Driven until it complained. Knocking, a ragged idle, smoke, a throttle that has gone soft. What you are hearing is the engine signalling fuel that no longer acts like diesel. Pull up wherever you are — the verge on Back Latch, a lay-by, a side street — then leave the car there. A car pulled over soon very seldom has permanent damage, since the drain and the flush-through, which still go first, deal with it.
What Bridgend motorists get told about petrol in a diesel — and the myths in it
Myth: topping up to full with diesel makes it fine. It does not. Topping up removes nothing; it gives you a fuller tank of the same mix. Percentage is not how a diesel fuel system copes with petrol, whatever that advice supposes.
If anything, the reverse holds. Myth: "A modern diesel can cope with a bit of petrol." At higher pressure, through more precise components: that's how a modern diesel handles its fuel, and so the protection matters more, not less.
The myth that catches motorists off guard: if it starts and drives, it must be unharmed. The driver of a petrol engine fed diesel usually stops, since it will not run, and the harm stops there. A diesel fed petrol generally starts, idles and drives away as though nothing has happened, whilst your pump wears. Being able to run isn't the same as being fine.
Not so: a two-stroke additive makes it safe to drive home. It was an old fix, meant for another fault. None of what petrol weakened is put back by it — and afterwards, that tank still contains that petrol.
Myth: "Drain that tank yourself and you are sorted." After the engine has run, some of the petrol is no longer in your tank: it is in the fuel filter and your lines, and it goes right back through the pump at the next start. It is also really hazardous to drain petrol into a can by the roadside.
How it happens: petrol in a diesel
Nobody does it on purpose, and it's rarely carelessness. A diesel nozzle mostly won't go into a petrol car, yet the smaller petrol nozzle goes into the filler of a diesel almost without resistance — so forecourts make this one error straightforward, and just in one direction.
It occurs when habit and your car stop matching. Courtesy car, hire car, or a motor that's new. One petrol and one diesel on the drive of the same household. A forecourt you know, only with its pumps laid out differently. Rushing for a train outside Cupar and filling up en route. A new-to-you diesel Renault Megane, its first fuelling, and a motorist accustomed to petrol: precisely when it happens. With rain, a call arriving, or children to deal with, your hand just does what it always has.
Bridgend drivers: how to avoid petrol in a diesel next time
- Not every forecourt in the UK follows green for unleaded and black for diesel, though most usually do. Read the pump's label; the colour is just a clue.
- The first fill in a strange vehicle is the time to check your filler flap — on it, or on the cap, many motors state which fuel to use.
- Label the key. In a household with one of each, a coloured fob or a sticker on your diesel's key does more than any amount of meaning to remember.
- "Diesel", out loud, before you lift the nozzle — each time a new or hired car needs its first tank. It sounds daft. It does the trick.
- Put the phone away. This is an easy mistake to make while you are thinking about something else.
- Some diesels have a filler built to block a petrol nozzle, and devices you can add are available for motors 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 that tank makes a thinner mix. What to do next doesn't change, though — still don't fire it up.
Petrol already in a diesel in Bridgend? Begin here
Then the order of things is brief. Don't turn your ignition on, and do not crank it. The attendants at the forecourt — whether at Tesco itself or wherever you filled up — will usually help push it away from the petrol pump if you ask. Call 0333 366 0103 next, with three facts — the fuel, the rough amount, and if it has run.
Corrosion and deposits are the issue with AdBlue, where petrol brings lost protection. So if it was AdBlue, say so — and read its own Bridgend page.
Why one petrol in a diesel task in Bridgend costs more than another
Four separate tasks lie behind the four situations above — which is why there is no fair single price. What shifts the cost is mostly which of them you're in. Two things come after that: the petrol that went in as a share of what that tank holds, then the place the car is in and whether a van can reach it safely.
Three questions come first, before any quote, instead of after — what went in, how much, has it run — and that is the reason. With those answers, there is a straight figure instead of a range.
About Bridgend, for a moment
Bridgend is a suburban area in Fife, situated on the riverside at an elevation of 79 metres, with detached housing being the predominant type of accommodation. Bridgend is located near several small villages, including Baltilly, Ceres, and Craigrothie, and is approximately 11 miles from the city of Dundee. Bridgend has a population of around 711 residents, who enjoy the scenic riverside setting. Bridgend is also relatively distant from major cities in England, with London being around 350 miles away.
Bridgend and Fife: where our fuel drain cover runs
Baltilly, Ceres and Craigrothie are among the locations around Bridgend that the same teams work, answering petrol in diesel jobs across Bridgend's KY postcode area. The car does not need to move to us: our technicians drain at a forecourt, in a supermarket car park, in a lay-by or on your own driveway.
Bridgend: still at the pump?
Then you're in the best position there can be. Keep it off. Call.