Should You Worry? Petrol in a Diesel Car in Winterborne Kingston
Unstarted? Then less anxious than you probably feel. Petrol sitting in a diesel tank does nothing to your engine until something pulls it through the fuel system — the ignition priming your pump, your starter, or the drive itself. So the honest answer to the first question anyone around Winterborne Kingston asks, "have I ruined it?", is generally no. Petrol in Diesel is who to phone, with your engine left off, so it remains that way. The remainder of this page sets out what petrol actually does to a diesel, how to judge how far it has got, and how to make sure it does not happen to you again.
Petrol in a diesel: what does it do to the motor?
On its way through an engine, diesel does two tasks. It lubricates first, and only then does it burn. Very fine clearances are built into the fuel injectors and the high-pressure pump, and only the diesel running through keeps those surfaces from grinding together.
Petrol handles the first task poorly and the second not at all. Being less viscous than diesel, petrol strips away the lubrication a fuel system needs, leaving a pump running on the blend wearing itself. It is also made to resist igniting under compression — the opposite of what a diesel needs — which is where you get the clattering.
Together, those leave the shape of the problem clear. The harm is done by circulation, not by contact. A tank with petrol in it is a fuel problem. The start of a mechanical problem is a pump that has been running on that petrol — and whatever a worn pump sheds moves on with the fuel to your injectors beyond it.
Four situations our engineers see in Winterborne Kingston: how bad is petrol in a diesel?
Filled up, never started. The best case there is. Only that tank has petrol in it, so the task is draining your tank and purging the system where the car sits. This scenario can only really happen at a forecourt: anywhere else, your car got there by being driven.
A brief spell of running, or merely your ignition on. With the system primed, your lines and filter now contain petrol that came from your tank. Drain, flush, see to the filter: still usually straightforward.
A couple of miles driven, and the pump has spent each of them labouring on diluted fuel. Tank, lines, filter, then fresh fuel put through the entire system: that is the work, and the way your car was driven counts as much as the distance. Driving the children to Bere Regis Primary and Preschool is one kind of trip. Any miles on the M27, under 50 miles from Winterborne Kingston, means the motor has worked hard throughout, and a run to Salisbury, under 50 miles away, makes a very different job as well.
Driven until it protested. Rattling, 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. Stop on the spot — on the verge on Plumbley Meadows, at the kerb, down a side road — and do not move it again. Permanent damage is very unusual if a car is stopped quickly, and the fuel drain and flush-through that still come first sort it out.
Stories Winterborne Kingston motorists hear about petrol in a diesel
Myth: topping up to full with diesel makes it fine. It doesn't. Nothing is removed when you top up — your tank simply holds more of the same blend. A diesel fuel system doesn't accept petrol by percentage in the way that guidance presumes.
Not so: a newer diesel copes with a bit of petrol. Rather, the opposite. Finer parts and higher pressure are the way a modern diesel runs its fuel, and that makes the protection matter more, not less.
"It starts, it drives, so no harm done" — the myth that trips up more motorists than any other. The motorist of a petrol motor fed diesel normally has no choice but to stop, because it will not run, and the damage stops there. A diesel fed petrol generally starts, ticks over and drives away as though nothing has happened, whilst the pump wears. Running is not 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 different issue. What petrol has diluted stays weakened, and that petrol stays in your tank regardless.
Myth: "Drain the tank yourself and you are sorted." After the engine has run, some of the petrol is no longer inside that tank: it's in your filter and the lines, and it goes straight back through your pump at your next start. Besides, petrol cleared into a can by the road is genuinely risky.
Petrol in a diesel: how does it occur?
On purpose? Never. Through carelessness? Seldom, if ever. A diesel nozzle mostly won't fit a petrol motor, but the slimmer petrol nozzle goes into the filler of a diesel nearly without resistance — so forecourts make this one mistake simple, and only in one direction.
The moment routine stops matching the car is the moment it occurs. Any vehicle that is new to you — a hire car, on loan as a courtesy car, or just bought. Households running one of each, petrol and diesel. A forecourt you know, only with its pumps laid out differently. A hurried fill on the way to Wool with a train to catch. A new-to-you diesel Renault Megane, its first fuelling, and a motorist used to petrol: exactly when it takes place. Throw in a back seat full of children, a phone call or rain, and the hand takes over.
How to avoid petrol in a diesel at your next fill-up around Winterborne Kingston
- A green handle for unleaded and black for diesel is usual in the UK — yet not on every forecourt. Trust the label on the petrol pump, not the colour.
- Many cars state the fuel type inside your filler flap or on the cap, so check it on your first fill in any car you do not know.
- Label your key. In a house with one of each, a coloured fob or a sticker on the diesel's key does more than any amount of intending to remember.
- "Diesel", aloud, before you lift the nozzle — every time a new or hired car gets its first tank. It seems daft. It works.
- Thinking about something else is when this becomes an easy mistake to make, so tuck the phone away then keep your mind on the pump.
- Up to a point, a misfuel inhibitor helps: some diesels have a filler designed to block a petrol nozzle, and aftermarket devices exist for the remainder. Count it as a safety net, and keep reading the pump.
- Stop the moment you realise. Less petrol inside that tank means a weaker mixture. It doesn't change what to do next, which is still not to fire it up.
Petrol already in a diesel in Winterborne Kingston? Start here
Then, there is only a short order of things. Leave it unstarted, with the ignition switched off too. Yet on the forecourt, at Shell or anywhere else? Ask the attendants to help you roll the vehicle clear of the pump. Ring 0333 366 0103 next, with three answers — your fuel, the approximate quantity, and if it has run.
AdBlue, not petrol? Then say so. Corrosion and deposits, not lost protection, make it a separate problem — Winterborne Kingston has a page just for it.
Why one petrol in a diesel job around Winterborne Kingston costs more than another
The four situations above are four different jobs, so no single quote for this would be honest. The situation itself does most of the work of moving your cost. Two things come after that: the petrol that was put in as a share of what that tank holds, then the place the car is in and whether a technician 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 the replies, there is a straight figure rather than a range.
About Winterborne Kingston and where it is
Winterborne Kingston is a village situated in the south of Dorset, near the River Winterborne, at an elevation of 53 metres. Winterborne Kingston lies close to several smaller settlements, including Winterborne Muston, Anderson, and Winterborne Tomson, and is approximately 26 miles from Salisbury. Winterborne Kingston has a population of around 719 people, predominantly living in detached houses. Winterborne Kingston is located in a rural area, about 103 miles west of London.
Winterborne Kingston and Dorset: where our fuel drain cover runs
The teams answering petrol in diesel calls in Winterborne Kingston, in the DT postcode area, equally work the places near it, Winterborne Muston, Anderson and Winterborne Tomson among them. The car doesn't 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.
At the pump around Winterborne Kingston, still?
Then, you could not be in a better place. Keep it off. Call.