Should You Worry? Petrol in a Diesel Car in Petersburn
Not started? Then less worried than you likely are. Petrol resting in a diesel tank does nothing to the engine till something pulls it through the system — your ignition priming the pump, the starter, or driving itself. So the honest answer to the first question everyone in Petersburn asks, "have I ruined it?", is normally no. To keep it that way, ring Petrol in Diesel and leave your motor switched off. What petrol actually does to a diesel, how to gauge how far it has gone, and how to keep it from happening again: that's the remainder of this page.
The engine and petrol in a diesel: what happens
On its way through an engine, diesel does two tasks. It protects to begin with, and only then does it burn. Made to extremely fine clearances, the injectors and the pump rely on your diesel moving through them to stop their surfaces wearing against one another.
Petrol does the first job poorly and the second not at all. Being less viscous than diesel, petrol strips away the lubrication a fuel system needs, leaving a pump on that mixture wearing itself. It is equally made to resist igniting under compression — the reverse of what a diesel needs — which is why you hear the clattering.
The shape of the issue is clear when you put those together. The harm is done by movement, not by contact. All a tank with petrol in it amounts to is a fuel issue. Once your pump has been labouring on that petrol, a mechanical fault has begun: anything shed by a pump that's wearing down is carried downstream to the injectors with the fuel.
How serious is petrol in a diesel? Four situations our engineers see in Petersburn
The best case there can be: filled up, not once started. Being on a forecourt is what makes this possible: elsewhere, the car has been driven there to begin with. With the petrol kept inside your tank alone, it's cleared and cleaned on the spot, and nothing more is needed.
A brief spell of running, or merely your ignition on. With the fuel system primed, the fuel lines and filter already contain petrol that has come from your tank. Still normally straightforward: drain, flush, and the filter sorted.
Your pump now spent a couple of miles on diluted fuel — that's what driving the vehicle does. How hard the vehicle was driven matters as much as how far, and the work takes in the tank, your lines, your filter and clean fuel through the whole circuit. Driving the kids to the local primary school is one kind of trip. Getting as far as Glasgow, under 15 miles away, makes a very different task — as does any mileage on the M8, under 3 miles from Petersburn, with the engine working hard all the way.
Clattering, an uneven idle, smoke, a throttle gone soft: driven until it complained. The fuel isn't acting like diesel any more, and the engine is telling you. Whether it's the verge on North Calder Drive, a lay-by or a side street, stop there and leave it. What comes first is still the fuel drain and flush-through, and that takes care of it, with permanent damage very rare when a car is pulled over soon.
What Petersburn motorists get told about petrol in a diesel — and the stories in it
False: topping up to full with diesel makes it fine. It doesn't. Nothing is removed when you top up — that tank just carries more of the same mixture. Percentage isn't how a diesel fuel system copes with petrol, however much that guidance supposes.
If anything, the reverse is true. Myth: "A modern diesel can cope with a bit of petrol." Finer components and higher pressure are how a newer diesel runs its fuel, and that makes the lubrication matter more, not less.
"It starts, it drives, and so no harm done" — the myth that trips up more drivers than any other. Diesel in a petrol motor normally means a motor that will not run: the driver stops, and so does the damage. Nothing looks to have happened when a diesel fed petrol fires up, ticks over and drives away, which it usually will; meanwhile your pump wears. Being able to run isn't proof of being fine.
An outdated workaround for a different fault lies behind this one. Myth: "Add some two-stroke oil and drive the car home." None of what petrol diluted gets put back by it — and afterwards, your tank still holds the petrol.
Myth: "Drain that tank yourself and you are sorted." Once the motor has run, some of the petrol is no longer in the tank: it's in the filter and the fuel lines, and it goes right back through your pump on your next start. And, a can of petrol filled by the roadside is genuinely risky.
Petrol in a diesel: how does it occur?
On purpose? Never. Through carelessness? Rarely, if ever. One way only, since of the nozzles: the slimmer petrol one slides inside a diesel filler with almost no resistance, whereas the diesel one mostly won't fit a petrol vehicle. That is how the forecourt makes it simple.
When routine and the car stop matching, it occurs. A new vehicle, a hire car or a courtesy car. Households running one of each, petrol and diesel. A forecourt you know, but with its pumps arranged differently. Fuelling up in a rush en route to Drumgelloch, with a train to catch. The first fill-up in a diesel Renault Clio after years of driving petrol is precisely the moment it takes place. Throw in rain, a phone call or a back seat full of kids, and the hand does what it has always done.
Petersburn motorists: how to prevent petrol in a diesel next time
- Check 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 counts.
- Many cars state the fuel inside your filler flap or on the cap, so check there on your first fill in any motor you don't know.
- Good intentions count for less than a sticker or a fob in a bright colour on your diesel's key if a house has one of each. So label it.
- Say it before you lift it. On your first fill in a new or hired car, say "diesel" aloud before you take the nozzle off the petrol pump. It seems daft and it does the trick.
- While you are thinking about something else, this is an easy mistake to make — so tuck your phone away.
- A misfuel inhibitor helps, up to a point. Some diesels have a filler built to reject a petrol nozzle, and add-on devices exist for cars without one. They are a safety net, not a reason to stop checking the pump.
- As soon as you realise, stop: less petrol inside the tank makes a thinner blend. What to do next doesn't change, though — still do not crank it.
Petrol already in a diesel around Petersburn? Begin here
In that case, there's just a short order of things. Leave it unstarted, with your ignition off as well. Ask the attendants to help you roll it away from the pump if you are still at the forecourt, whether that is BP or anywhere else. Next, 0333 366 0103. We will ask what was put in, roughly how much, and if it has been run.
Corrosion and deposits are the trouble with AdBlue, where petrol brings lost lubrication. So if it was AdBlue, say so — and see its own Petersburn page.
One petrol in a diesel job in Petersburn costs more than another. Why?
A fair single price does not exist here: four situations, four separate tasks. Which of them you're in is mostly what shifts the cost. Two things follow that: the petrol that went in as a proportion of what the tank holds, then the spot your car is in and whether a van can get to it safely.
Before any quote, not after, we ask three queries: the fuel that went in, its amount, and whether it has run. That's why. Their answers are what change a range into one firm number.
About Petersburn and its setting
Petersburn is a suburban area situated on the riverside in North Lanarkshire, with a mix of terraced housing and local amenities. Petersburn sits at an elevation of 158 metres, close to the nearby communities of Craigneuk and Gartness. Petersburn is located approximately 11 miles from Glasgow, making it a commuter-friendly location. Petersburn has a population of around 5917 people, with a range of local services and facilities.
Fuel drain cover across North Lanarkshire, Petersburn included
Our vans answering petrol in diesel jobs in Petersburn, in the ML postcode area, equally work the locations near it, Craigneuk, Dunrobin and Gartness among them. The vehicle does not need to come to us: our technicians drain at a forecourt, in a supermarket car park, in a lay-by or on your own driveway.
Petersburn: still at the pump?
Then you're in the best position there is. Keep it switched off, and ring.