Petrol in a Diesel Car in Headington: How Worried Should You Be?
Far less than you likely are, provided it has not been started. "Have I ruined it?" is the first thing anyone in Headington asks, and the honest answer is generally no, since petrol left in a diesel tank harms nothing till it is dragged through the fuel system — by ignition priming, by your starter, or by driving. Keep it like that: leave your engine off and phone Petrol in Diesel. Keep reading for three things: the effect petrol has inside a diesel motor, the clues of how far it has spread, and ways to make sure you never do it again.
Petrol in a diesel: what does it do to the motor?
Diesel has two tasks on its way through a motor. Oiling comes before burning; it does both. Extremely fine clearances go into the injectors and the high-pressure pump, and just the diesel flowing through stops those surfaces grinding together.
Of these two jobs, petrol handles the first badly and the second never. A pump running on a petrol blend is wearing itself out, since petrol is thinner than diesel and takes away the protection the fuel system relies on. Petrol is also made to resist igniting under compression — the reverse of what a diesel needs from its fuel — and that is where any rattling starts.
Seen together, they show what shape the problem has. The harm is done by movement, not by contact. Petrol in the tank is a fuel problem. Whatever a worn pump sheds goes on, borne by your fuel, into the fuel injectors further along, which is why a pump that has worked on that petrol is where a mechanical issue starts.
Petrol in a diesel around Headington: how bad is it? Four cases
The best case there is: filled up, never started. The petrol is in that tank and only your tank, and the job is a drain and a flush where the car stands. This is the one scenario that can only really happen on a forecourt, since anywhere else the vehicle has been driven to get there.
A moment's running, or merely your ignition on. Your system has been primed, and so petrol has left that tank and got to the fuel filter and the fuel lines. Still usually straightforward: drain, flush, and your filter dealt with.
Those few miles driven were the pump running on fuel diluted by petrol the whole way. How hard your car was driven matters as much as how far, and the work takes in that tank, the fuel lines, the fuel filter and fresh fuel through the whole system. Driving the children to St Andrew's Church of England Primary School, Oxford is one kind of trip. Getting as far as Oxford, under 3 miles away, makes a very different task — as does any distance on the M40, under 5 miles from Headington, with your engine labouring hard the whole time.
Driven on until it complained — rattling, smoke, a lumpy idle, a soft throttle. The engine is telling you your fuel is no longer behaving like diesel. Stop wherever you are — the verge on Osler Road, a lay-by, a side street — then leave the vehicle where it is. What goes first is still the fuel drain and flush, and that takes care of it, with permanent damage very uncommon when a vehicle is pulled over soon.
Stories Headington motorists hear about petrol in a diesel
Myth: topping up to full with diesel makes it fine. It doesn't. Topping up takes out nothing; it gives you a fuller tank of the same mix. A diesel fuel system doesn't accept petrol by percentage in the way that guidance supposes.
Myth: "A current diesel can cope with a bit of petrol." If anything, the opposite. Smaller parts and higher pressure are the way a current diesel runs its fuel, and that makes the protection matter more, not less.
One myth that catches people off guard: if it starts and drives, it must be unharmed. A petrol engine fed diesel generally won't run, so the motorist stops and the harm stops with them. Feed petrol to a diesel and it usually starts, ticks over and pulls away like nothing happened — all the while its pump wears. Fine and running aren't the same at all.
Not so: a two-stroke additive makes it safe to drive home. It is an old workaround, supposed for another problem. It does not put back what petrol has weakened, and that petrol is still inside that tank later on.
If your engine has been run, part of that petrol sits in your filter and the fuel lines, not that tank — and your next start pulls it right back through your pump. So the myth "drain your tank yourself and you are sorted" does not hold. Also, a can of petrol drained by the roadside is truly risky.
Petrol in a diesel: how does it happen?
It is seldom carelessness, and nobody does it on purpose. The forecourt makes it easy: the petrol nozzle is the smaller of the two, and it slips into a diesel filler with almost no resistance, while a diesel nozzle generally will not go into a petrol vehicle at all. So the mistake runs one way.
Habit and your car falling out of step is when it occurs. A new car, a hire car or a courtesy car. A household with one petrol and one diesel on the drive. The pumps in a different order on a well-known forecourt. A rushed fill on the way to Oxford with a train to catch. A new-to-you diesel Renault Clio, its first fuelling, and a driver used to petrol: precisely when it happens. The hand repeats what it has always done once you add rain, a phone call or a back seat full of kids.
How to avoid petrol in a diesel at your next fill-up in Headington
- Green for unleaded and black for diesel is usual in the UK — yet not on every forecourt. Go by the label on the petrol pump, not the colour.
- The first fill in a strange vehicle is the time to check your filler flap — on it, or on the cap, plenty of vehicles state which fuel they take.
- Good intentions count for less than a sticker or a fob in a bright colour on the diesel's key if a household has one of each. So label it.
- "Diesel", aloud, before you pick up the nozzle — each time a new or hired car gets its first tank. It seems silly. It does the trick.
- Tuck the phone away. This is an easy mistake to make whilst you are thinking about something else.
- Up to a point, a misfuel inhibitor helps: some diesels come with a filler built to refuse a petrol nozzle, and aftermarket devices are available for the remainder. Count it as a backstop, and keep checking the pump.
- Spotting it mid-fill? Stop there and then. A thinner mixture results from less petrol in that tank, but the next step stays the same: don't start it.
Put petrol in a diesel around Headington already?
The order of things is brief, then. Don't switch the ignition on, and do not crank it. The staff at the forecourt — whether at Shell itself or wherever you filled up — will normally help roll it clear of the pump if you ask. What got in, roughly how much, and whether it has run: tell us those when you call 0333 366 0103.
If it was AdBlue and not petrol, say so. That's a separate issue — corrosion and deposits instead of lost protection — and it has its own page for Headington.
Why one petrol in a diesel task around Headington costs more than another
The four situations above are four separate jobs, so no single price for this would be honest. Which of them you are in is mostly what shifts your cost. Next it's the share — how much petrol went in against how much that tank takes — and then where the car is and whether our van can reach it safely.
Three questions come first, before any quote, rather than after — what went in, how much, has it run — and that is the reason. A range turns into a straight figure once those replies are in.
About Headington and where it is
Headington is a suburban area located on the outskirts of Oxford, situated near the River Cherwell in South East England. Headington sits at an elevation of 104 metres, with its semi-detached housing stock characteristic of the area's residential development. Headington is close to several nearby places, including Headington Quarry and New Headington, and is just 2.1 miles from Oxford city centre. Headington has a population of approximately 6128 residents.
Across Oxfordshire and around Headington: fuel drain cover
Petrol in diesel call-outs in Headington — part of the OX postcode area — go to teams that also cover the places round it, Headington Quarry, New Headington and Sandhills included. You need not move your car to us. Forecourts, supermarket car parks, lay-bys and your own driveway are all locations where we work.
In Headington and still at the pump?
The best place there is, then — that is where you are. Keep it off. Phone.