Northend: Petrol in a Diesel Car? How Worried to Be
If it hasn't been started, you can worry far less than you probably are. Petrol sitting in a diesel tank does nothing to the motor until something pulls it through your fuel system — the ignition priming the pump, your starter, or driving itself. So the truthful answer to the first question everyone in Northend asks, "have I wrecked it?", is normally no. Leave the motor off and call Petrol in Diesel — that keeps it that way. The remainder of this page covers what petrol really does to a diesel, how to judge how far it has got, and how to make sure it does not happen to you again.
Inside the motor: what petrol in a diesel really does
Two jobs fall to diesel on its journey through a motor. Lubricating comes before burning; it does both. What keeps the surfaces inside the high-pressure pump and the injectors from wearing against each other is the diesel passing through them — they are made to extremely fine clearances.
Of those two jobs, petrol manages the first badly and the second not at all. It's thinner than diesel and removes the lubrication the system hinges on, and so a pump running on a petrol mix 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's where the rattling comes from.
The shape of the issue is clear once you put those together. Contact does not do the harm — circulation does. All a tank with petrol in it amounts to is a fuel problem. Whatever a worn pump sheds travels on, carried by your fuel, into the fuel injectors further along, which is why a pump that has been working on that petrol is where a mechanical fault begins.
Northend, petrol in a diesel: four situations, from mild to significant
Filled up, and never started: nothing beats it. Being at a forecourt is what makes this the case: elsewhere, the car has been driven there to begin with. With the petrol held in that tank alone, it is emptied and flushed right where it stands, and nothing more is needed.
Ignition on, or started for a moment. Once primed, the fuel system has drawn petrol from the tank up to the fuel filter and your lines. Drain, flush, see to your filter: still usually straightforward.
Driven a couple of miles. Now the pump has spent these miles working on diluted fuel. Tank, lines, filter, then clean fuel run through the entire circuit: that's the work, and the way the car was driven matters as much as the distance. Driving the kids to St Leonard's Church of England Primary School is one sort of trip. Very different again: a run to Southend-on-Sea, under 15 miles away, or any mileage on the M2, under 25 miles from Northend, where the engine never stopped working hard.
Driven until it protested. Rattling, a lumpy idle, smoke, a throttle that has gone soft. The fuel isn't behaving like diesel any more, and the motor is saying so. Whether it's the verge on Sheepcotes Lane, a lay-by or a side street, stop there then leave it. A car stopped soon very seldom has long-term damage, as the drain and the flush-through, which still go first, deal with it.
What Northend people get told about petrol in a diesel — and the myths in it
Myth: topping up to full with diesel makes it fine. It doesn't. A fuller tank of the same mix is all you get, since topping up takes out nothing. The assumption behind the advice — that diesel fuel systems tolerate petrol by percentage — is wrong.
Myth: "A modern diesel can cope with a bit of petrol." If anything, the reverse. Lubrication counts more on current diesels, not less, since their fuel passes through more precise parts at higher pressure.
The myth that catches drivers out: if it starts and drives, it must be unharmed. Feed diesel to a petrol engine and it usually will not run, so the motorist stops — and the harm stops with them. A diesel fed petrol usually starts, idles and drives away as though nothing has happened, while the pump grinds. Fine and running aren't the same thing.
Not so: a two-stroke additive lets you to drive home. It was an old fix, meant for another problem. That petrol is still inside the tank afterwards, and what it has weakened is not put back.
If the engine has been run, part of that petrol is in your filter and your lines, not that tank — and your next start pulls it straight back through the pump. So the myth "drain the tank yourself and you're sorted" doesn't stand up. It is also really dangerous to drain petrol into a can at the roadside.
Petrol in a diesel: how does it take place?
Nobody does it on purpose, and it's rarely carelessness. One way only, because of the nozzles: the slimmer petrol one slips inside a diesel filler with almost no resistance, while the diesel one mostly won't fit a petrol vehicle. That is how the forecourt makes it easy.
The moment habit stops matching your car is the moment it takes place. Hire cars, courtesy cars, and motors that are new to you. Households running one of each, petrol and diesel. Your normal forecourt, its pumps suddenly in a different order. Racing for a train at Southminster and filling up en route. The first fill-up in a diesel Volkswagen Passat after years of driving petrol is exactly the moment it happens. Add rain, a phone call or a back seat full of children, and your hand repeats what it has always done.
Preventing petrol in a diesel next time you fill up around Northend
- 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 every forecourt.
- Many motors state the fuel inside the filler flap or on the cap, and so check it on the first fill in a motor you don't know.
- A coloured fob or a sticker on your diesel's key does more than any amount of meaning to remember, in a house with one of each.
- It sounds silly and it works: on the first fill in a new or hired car, say "diesel" aloud before you take the nozzle off the pump.
- Whilst you're thinking about something else, this is an easy mistake to make — so put the phone away.
- Add-on devices are available for vehicles without one, and some diesels come with a filler that won't take a petrol nozzle. Helpful — but a safety net at best, never a reason to stop checking the label.
- Less petrol makes a thinner blend, and so stop as soon as you notice — while remembering that the next stage is unchanged. It's still not to crank it.
Put petrol in a diesel in Northend already?
In that case, there's just a short order of things. Leave it unstarted, with your ignition switched off as well. If you're still at the forecourt — Woodfords Garage or anywhere else — ask the staff to help you push it away from the pump. Ring 0333 366 0103 next, with three answers — the fuel, the approximate volume, and if it has run.
AdBlue, not petrol? Then say so. Corrosion and deposits, not lost lubrication, make it a separate issue — Northend has a page just for it.
One petrol in a diesel task around Northend costs more than another. Why?
A fair single price doesn't exist here: four scenarios, four separate tasks. The scenario itself does most of the work of moving your cost. Next it's the ratio — how much petrol went in against how much the tank takes — and after that where the car is and whether our van can get to it safely.
What was put in, how much, and if it has run — three questions our technicians ask before costing, not after, for precisely that reason. With the answers, there is a straight figure instead of a range.
About Northend and its setting
Northend is a suburban area in Essex, situated approximately 42.6 miles from London and 10 miles from the city of Southend-on-Sea. Northend lies inland, with an elevation of around 27 metres, and is characterised by its predominantly semi-detached housing stock. Northend is located near other small settlements such as Southminster, Cripplegate, and Asheldham, and has a population of around 3295 residents.
Northend and Essex: where our fuel drain cover runs
Southminster, Cripplegate and Asheldham are among the places around Northend that the same teams work, answering petrol in diesel call-outs across Northend's CM postcode area. A forecourt, a supermarket car park, a lay-by or your own drive are all spots our engineers work, and your vehicle does not need to move to us.
Still at the petrol pump in Northend?
The best spot there is, then — that's where you are. Keep it off. Call.