Should You Worry? Petrol in a Diesel Car in Portobello
If it has not been started, you can worry less than you probably are. "Have I wrecked it?" is the first question anyone around Portobello asks, and the truthful answer is usually no, since petrol resting in a diesel tank hurts nothing until it is dragged through the fuel system — by ignition priming, by your starter, or by driving. Petrol in Diesel is who to ring, with your engine kept off, and so it stays that way. What petrol really does to a diesel, how to gauge how far it's travelled, and how to stop it from happening a second time: that is the remainder of this page.
Inside the engine: what petrol in a diesel does
On its way through a motor, diesel does two jobs. It protects first, and after that does it burn. What stops the surfaces inside the high-pressure pump and your injectors from wearing against each other is your diesel passing through them — they are built to very fine gaps.
Badly at the first, not at all at the second: that is petrol. It's thinner than diesel and takes away the protection the system rests on, so a pump running on a petrol blend is a pump wearing itself. And petrol is designed to resist igniting under compression, which is the reverse of what a diesel needs from its fuel. That is where the clattering comes from.
Put these together and the shape of the problem is clear. Not contact but circulation is what does the damage. Where the petrol is only in your tank, it is a fault of fuel, nothing more. After your pump has been working on that petrol, a mechanical problem has started: whatever is shed by a pump that is grinding is carried downstream to your injectors with the fuel.
How bad is petrol in a diesel? Four scenarios our technicians see in Portobello
Filled but not once started — the best it gets. Being on a forecourt is what makes this the case: elsewhere, your car has been driven there to begin with. With the petrol held inside your tank alone, it's emptied and cleaned right where it stands, and nothing more is needed.
A brief spell of running, or just your ignition on. With the fuel system primed, the fuel lines and filter already hold petrol that came from your tank. Still generally simple: drain, flush, and the fuel filter sorted.
Some miles driven, and the pump has spent every one of them labouring on thinned fuel. Mileage is only half of that; how hard it was driven counts just as much. Either way the work includes your tank, the lines, the fuel filter and fresh fuel through the whole system. The school run to the local primary school is one matter. Very different a second time: a trip to Edinburgh, under 3 miles away, or any miles on the M8, under 10 miles from Portobello, where the engine never stopped labouring hard.
It protested, and only then stopped: smoke, rattling, a throttle gone soft, an idle gone uneven. The engine is telling you your fuel is no longer behaving like diesel. Leave it wherever it stops: a lay-by, a side street, the verge on Rosefield Place. Lasting damage is very rare when a vehicle is pulled over quickly, and the drain and flush that still come first take care of it.
Stories Portobello motorists hear about petrol in a diesel
False: topping up to full with diesel makes it fine. It does not. Nothing comes out when you top up — the tank just carries more of the same mixture. That guidance supposes a diesel fuel system handles petrol by percentage. It does not.
"Modern diesels can handle a little petrol" — a myth, and closer to the reverse. Protection counts more on newer diesels, not less, since their fuel runs through smaller components at higher pressure.
The myth that catches motorists off guard: if it starts and drives, it must be unharmed. The driver of a petrol engine fed diesel normally has no choice but to stop, since it will not run, and the damage stops with them. While your pump grinds, a diesel fed petrol normally starts, ticks over and drives away as if nothing has happened. A running engine doesn't mean fine.
Myth: a two-stroke additive lets you to drive home. It was an old fix, meant for another problem. It doesn't put back what petrol has weakened, and that petrol is still inside that tank after that.
Myth: "Drain the tank yourself and you are sorted." Once your engine has been run, some of that petrol is no longer in the tank: it is in your filter and the fuel lines, and it goes right back through the pump on your next start. Also, a can of petrol drained at the roadside is genuinely dangerous.
Why petrol in a diesel happens at all
On purpose? Never. Through carelessness? Rarely, if ever. A diesel nozzle generally won't go into a petrol vehicle, yet the slimmer petrol nozzle goes into the filler of a diesel almost without resistance — so forecourts make this one mistake simple, and just in one direction.
It happens when routine and your car stop matching. Courtesy car, hire car, or a vehicle that's brand new. Households running one of each, petrol and diesel. Your usual forecourt, its pumps now in a different order. A train to catch, and a hurried fill on the way to Brunstane. The first fill-up in a diesel Volkswagen Golf after years of driving petrol is exactly the moment it takes place. Throw in rain, a phone call or a back seat full of children, and your hand does what it has always done.
Portobello people: how to prevent petrol in a diesel next time
- The label is what matters, so read the pump instead of the colour: in the UK unleaded handles are normally green and diesel black, yet not on each forecourt.
- The first fill in a strange motor is the time to check your filler flap — inside it, or on the cap, plenty of vehicles state the fuel to use.
- Mark 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 intending to remember.
- "Diesel", out loud, before you lift the nozzle — each time a new or hired car gets its first tank. It sounds daft. It works.
- Put the phone away. This is an easy mistake to make while you are thinking about something else.
- Add-on devices are available for motors without one, and some diesels come with a filler that won't accept a petrol nozzle. Helpful — but a safety net at best, never a reason to stop checking the label.
- Less petrol means a thinner mix, and so stop as soon as you notice — while remembering that the next stage is unchanged. It is still not to start it.
Portobello: already put petrol in a diesel?
Short and simple, then, is the order of things. Do not fire it up, and do not turn your ignition on. The staff at the forecourt — whether at Esso itself or wherever you filled up — will usually help roll it clear of the pump if you ask. Ring 0333 366 0103 next, with three answers — your fuel, the rough volume, and whether it has run.
AdBlue, not petrol? Then tell us. Corrosion and deposits, not lost lubrication, make it a separate issue — Portobello has a page just for it.
Portobello petrol in a diesel tasks: why one costs more than another
There is no fair single quote for this, because the four situations above are four separate jobs. Mostly, the cost moves with which one you are in. The ratio counts next, meaning how much of that tank is petrol, followed by the location of the car and whether getting to it is safe for our van.
That's why we ask three questions before costing instead of after: what got in, how much, and whether it's run. The replies turn a range into a straight figure.
About Portobello and where it is
Portobello is a coastal suburban area in the City of Edinburgh, situated approximately 2.8 miles from Edinburgh's city centre. Portobello has a relatively low elevation of 14 metres and is characterised by its predominantly flat-type housing. Portobello is close to nearby places such as Duddingston, Northfield, and Piershill, and is home to a population of around 5930 people.
Portobello and City of Edinburgh: where our fuel drain cover runs
Our vans answering petrol in diesel call-outs around Portobello, in the EH postcode area, equally work the places near it, Duddingston, Northfield and Piershill among them. A forecourt, a supermarket car park, a lay-by or your own driveway are all spots our engineers work, and your vehicle does not need to come to us.
At the pump around Portobello, still?
Then you are in the best spot there can be. Call, and leave it switched off.