Petrol in a Diesel Car in The Rigg: How Worried Should You Be?
Likely less than you are now — provided no one has started the vehicle. Petrol sitting in a diesel tank does nothing to the engine until something pulls it through the fuel system — the ignition priming your pump, the starter, or the drive itself. So the fair answer to the first query anyone around The Rigg asks, "have I ruined it?", is normally no. Petrol in Diesel is who to call, with the motor kept off, and so it stays that way. Keep reading for three things: the effect petrol has inside a diesel engine, the clues of how far it has spread, and ways to make sure you never do it again.
Your engine and petrol in a diesel: what happens
Two jobs fall to diesel on its journey through a motor. Before it combusts, it lubricates — and then it combusts. The high-pressure pump and your injectors are built to very fine gaps, and the diesel passing through them is what stops those surfaces from grinding against one another.
The second task petrol doesn't do at all, and the first it does poorly. The clattering comes from petrol being designed not to ignite when compressed, which is exactly the reverse of what a diesel needs. On top of that it is thinner than diesel, it strips out the lubrication the system rests on, and any pump working on that mix is wearing itself.
Seen together, they make clear the shape the issue takes. Contact doesn't do the damage — circulation does. Petrol in a tank is a fuel issue. Once your pump has been labouring on that petrol, a mechanical problem has begun: anything shed by a pump that is wearing is carried downstream to your injectors with the fuel.
Four scenarios our engineers see in The Rigg: how bad is petrol in a diesel?
Fuelled up, not once started. The best case there can be. That petrol is inside that tank and only your tank, and the task is a drain and a flush where your car stands. This is the one situation that can only truly occur at a forecourt, since anywhere else the vehicle has been driven to get there.
Started for a moment, or only your ignition on. Once primed, the system has pulled petrol out of the tank as far as the fuel filter and the lines. Normally little more than emptying, cleaning and seeing to the fuel filter, so still straightforward.
Your pump has worked a few miles on diluted fuel — that's what driving the car meant. Tank, lines, filter, then clean fuel run through the whole system: that's this work, and the way the vehicle was driven counts as much as the distance. Short trips, such as the school run to the local primary school, are one thing. Very different once more: a run to Glasgow, under 50 miles away, or some mileage on the M77, under 15 miles from The Rigg, where your engine never stopped running hard.
Driven till it complained. Knocking, an uneven idle, smoke, a throttle that has gone soft. The motor is telling you the fuel is no longer behaving like diesel. Pull up wherever you are — the verge on Rigg Road, a lay-by, a side street — then leave the vehicle where it is. A car stopped early very seldom has long-term damage, as the fuel drain and the flush-through, which still go first, deal with it.
The Rigg people and that petrol in a diesel myths they hear
Myth: topping up to full with diesel makes it fine. It doesn't. Topping up takes out nothing; it gives you a bigger tank of the same mixture. That advice assumes a diesel fuel system tolerates petrol by percentage. It does not.
Myth: a newer diesel copes with a bit of petrol. If anything, the reverse. Lubrication matters more on modern diesels, not less, because their fuel passes through finer components at higher pressure.
One myth that catches drivers off guard: if it starts and drives, it must be unharmed. The motorist of a petrol motor fed diesel usually stops, since it will not run, and the damage stops there. Nothing looks to have happened when a diesel fed petrol fires up, ticks over and drives away, as it usually will; meanwhile the pump wears. Running is not the same as fine.
Myth: "Add some two-stroke oil and drive it home." It's an outdated workaround for a separate problem. None of what petrol weakened gets put back by it — and afterwards, the tank still holds that petrol.
Myth: "Drain that tank yourself and you're sorted." After the motor has been run, some of that petrol is no longer inside the tank: it is in the fuel filter and the fuel lines, and it goes right back through the pump at the next start. On top of that, petrol drained into a can by the road is genuinely risky.
Why petrol in a diesel takes place so easily
Carelessness is seldom the cause, and no one means to do it. The forecourt makes it simple: the petrol nozzle is the narrower of the two, and it slides into a diesel filler with almost no resistance, while a diesel nozzle generally will not go into a petrol motor at all. So the error runs one way.
It happens when routine and the car stop matching. A car that's new to you — a hire car, on loan as a courtesy car, or just bought. Households running one of each, petrol and diesel. A familiar forecourt with the pumps in a different order. A rushed fill on the way to Auchinleck with a train to catch. The first fill-up in a diesel Volkswagen Tiguan after years of driving petrol is exactly the moment it takes place. With rain, a call arriving, or a car full of children to deal with, your hand simply does what it always has.
The Rigg drivers: how to prevent petrol in a diesel next time
- Green for unleaded and black for diesel is usual in the UK — yet not on every forecourt. Trust the label on the pump, not the colour.
- Inspect the filler flap. Many 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.
- One of each in the home? Label your key to your diesel — a bright fob, a sticker — since intending to remember isn't enough.
- Say it before you lift it. On your first fill in a new or hired car, say "diesel" aloud before you lift the nozzle off the pump. It seems daft and it works.
- Tuck the phone away. This is an easy mistake to make while you're thinking about something else.
- Up to a point, a misfuel inhibitor helps: some diesels come with a filler designed to refuse a petrol nozzle, and add-on devices exist for the remainder. Treat it as a backstop, and keep reading the petrol pump.
- Spotting it halfway? Stop there and then. A weaker blend results from less petrol in the tank, yet your next stage stays the same: don't crank it.
Already put petrol in a diesel in The Rigg?
Then the order of things is short. Starting it is out, and so is turning on the ignition. Still on the forecourt, at JET or anywhere else? Ask the attendants to help you roll the car away from the petrol pump. Call 0333 366 0103 next, with three facts — your fuel, the approximate quantity, and if it's run.
If it was AdBlue instead of petrol, say so. That's a separate fault — corrosion and deposits instead of lost protection — and it has its own page for The Rigg.
Why one petrol in a diesel task in The Rigg costs more than another
The four scenarios above are four separate tasks, so no single price for this would be fair. The situation itself does most of the work of moving the cost. The ratio counts next, meaning how much of that tank is petrol, followed by the position of your car and whether getting to it is safe for our van.
Three queries come first, before any quote, instead of after — what went in, how much, has it run — and this is the reason. Their answers are what change a range into one firm number.
About The Rigg and where it is
The Rigg is a small hamlet situated on the riverside in East Ayrshire, with a mix of detached housing and a population of around 683 residents. The Rigg sits at an elevation of 149 metres, near the communities of Knockroon, Holmhead, and Cumnock. The Rigg is located approximately 27.8 miles from Glasgow, making it a rural outpost within commuting distance of the city. The Rigg enjoys a scenic setting, with the surrounding countryside offering opportunities for outdoor activities.
Across East Ayrshire and in The Rigg: fuel drain cover
The Rigg sits in the KA postcode area, and our teams that answer petrol in diesel jobs there work the locations near it as well — Knockroon, Holmhead and Cumnock among them. The vehicle 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 driveway.
Still at the petrol pump in The Rigg?
The best place there is, then — that is where you are. Call, and keep it turned off.