Petrol in a Diesel Car in Birmingham: How Worried Should You Be?
Far less than you probably are, if it hasn't been started. Petrol sitting in a diesel tank does nothing to your engine till something pulls it through your fuel system — your ignition priming the pump, your starter, or the drive itself. So the honest answer to the first query everyone in Birmingham asks, "have I ruined it?", is generally no. To leave it that way, call Petrol in Diesel then leave the motor alone. Further down, you will find what petrol actually does inside a diesel, how far it might have gone, and how to stop it happening to you a second time.
What petrol in a diesel does to your engine
Two jobs fall to diesel on its journey through a motor. Oiling comes before burning; it does both. What stops the surfaces inside your high-pressure pump and the fuel injectors from wearing against each other is the diesel flowing through them — they are designed to extremely fine clearances.
Of these two tasks, petrol manages the first poorly and the second never. A pump running on a petrol blend is wearing itself out, because petrol is runnier than diesel and takes away the protection your fuel system relies on. Petrol is also made to resist igniting under compression — the reverse of what a diesel wants from its fuel — and that is where the clattering comes.
The shape of the trouble is clear once you put those together. Not contact but movement is what causes the damage. All a tank with petrol in it amounts to is a fuel issue. A pump that has been labouring on that petrol is the beginning of a mechanical one, and whatever a worn pump sheds travels on with the fuel to the injectors downstream.
Four scenarios we see around Birmingham: how bad is petrol in a diesel?
Filled but never started — as good as it gets. That petrol is in that tank and only your tank, and the task is a drain and a flush where the car stands. This is the one scenario that can only truly happen at a forecourt, because anywhere else the car has been driven to get there.
Started for a moment, or just your ignition on. Petrol has left the tank and reached the filter and the fuel lines, because the fuel system has been bled. That is normally still a simple job — a drain, a flush, and your filter dealt with.
The pump has spent a couple of miles on weakened fuel — that's what driving the car does. How hard your car was driven counts as much as how far, and the work takes in your tank, your lines, the filter and fresh fuel through the whole circuit. On the school run to St Catherine of Siena Catholic Primary School, the distance is short. Any miles on the Aston Expressway, under a mile from Birmingham, means your engine has worked hard throughout, and a run to Wolverhampton, under 15 miles away, is a very different job as well.
It complained, and only then stopped: smoke, knocking, a throttle gone soft, an idle gone lumpy. The fuel is not behaving like diesel any more, and your motor is telling you. Pull up where you are — on the verge on Hill Street, at the kerb, down a side road — and don't move it again. A vehicle stopped quickly very rarely has long-term damage, because the drain and the flush-through, which still go first, sort it out.
Birmingham motorists and the petrol in a diesel stories they hear
It will not be fine. The myth: "Fill it the rest of the way with diesel and it will be." Topping up takes out nothing; it gives you a bigger tank of the same mixture. The idea behind that advice — that diesel fuel systems accept petrol by percentage — is wrong.
"Current diesels can handle a little petrol" — a myth, and closer to the reverse. Lubrication matters more on newer diesels, not less, because their fuel runs through finer components at higher pressure.
"It starts, it drives, and so there is no harm" — the myth that trips up more motorists than any other. Feed diesel to a petrol engine and it usually will not run, and so the motorist stops — and the damage stops with them. While the pump grinds, a diesel fed petrol usually starts, ticks over and drives away as if nothing has happened. Running is not the same as fine.
Myth: "Add some two-stroke oil and drive the car home." It is an outdated fix for a different fault. What petrol has weakened stays weakened, and that petrol remains inside your tank anyway.
"Drain it yourself and you are sorted" — a myth, because after it's been running some petrol lies in your filter and lines, waiting to go straight back through the pump on your next start. It is also really hazardous to drain petrol into a can by the kerbside.
Why petrol in a diesel takes place at all
It's seldom carelessness, and nobody does it on purpose. The forecourt makes it easy: the petrol nozzle is the slimmer of the two, and it slips into a diesel filler with almost no resistance, whilst a diesel nozzle generally won't go into a petrol vehicle at all. So the error runs one way.
Habit and your car falling out of step is how it happens. Hire cars, courtesy cars, and vehicles that are new to you. Households running one of each, petrol and diesel. Your normal forecourt, its pumps suddenly in a different order. Fuelling up in a rush on the way to Birmingham New Street, with a train to catch. A new-to-you diesel Nissan Qashqai, its first fuelling, and a driver accustomed to petrol: precisely when it happens. Add a back seat full of children, a phone call or rain, and the hand takes over.
Birmingham drivers: how to avoid 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 each forecourt. The label is what matters.
- In a motor you do not know, look inside the flap over your filler or at the cap before your first fill: plenty of vehicles state the fuel type there.
- A coloured fob or a sticker on your diesel's key achieves more than any amount of intending to remember, for a household with one of each.
- It sounds silly and it works: on your first fill in a new or hired car, say "diesel" out loud before you lift the nozzle off the pump.
- Put your phone away. This is an easy mistake to make whilst you are thinking about something else.
- Some diesels have a filler built to block a petrol nozzle, and devices you can add are available for motors without one. Such an inhibitor helps up to a point — as a safety net, not a reason to stop checking the pump.
- The moment you notice, stop: less petrol inside that tank means a thinner mix. What to do next does not change, though — still don't crank it.
Already put petrol in a diesel in Birmingham?
Short and simple, then, is the order of things. Do not switch the ignition on, and don't start it. The staff at the forecourt — whether at Esso itself or wherever you filled up — will usually help roll it clear of the petrol pump if you ask. Then call 0333 366 0103 and tell us what was put in, roughly how much, and whether it has run.
If it was AdBlue rather than petrol, say so. That's a different problem — corrosion and deposits rather than lost protection — and it has its own page for Birmingham.
One petrol in a diesel job around Birmingham costs more than another. Why?
An honest single quote doesn't exist here: four scenarios, four separate tasks. Chiefly, your cost moves with which situation you are in. Two things follow that: the petrol that went in as a share of what the tank holds, then the spot the car is in and whether our van can get to it safely.
Before any quote, not after, come three queries: the fuel that got in, the amount, and if it has run. That's why. A range becomes a straight figure when those answers are in.
About Birmingham itself
Birmingham is a major city located in the West Midlands region of England, situated on the River Rea and River Tame. Birmingham sits at an elevation of around 146 metres, approximately 101 miles northwest of London. Birmingham is a densely populated urban area, with a mix of residential and commercial districts, including areas like Lee Bank, Ladywood, and Digbeth. Birmingham has a predominantly flat-based housing stock, reflecting its urban character.
Across West Midlands and in Birmingham: fuel drain cover
Petrol in diesel calls around Birmingham — part of the B postcode area — go to vans that also cover the locations round it, Lee Bank, Ladywood and Digbeth among them. The vehicle does not need to move to us: we drain on a forecourt, in a supermarket car park, in a lay-by or on your own driveway.
At the petrol pump around Birmingham, right now?
The best place there is, then — that's where you are. Phone, and leave it turned off.