Priorslee: Petrol in a Diesel Car? How Worried to Be
Less than you likely are, if it hasn't been started. "Have I wrecked it?" is the first thing anyone around Priorslee asks, and the truthful answer is usually no, since petrol resting in a diesel tank hurts nothing until it's dragged through the fuel system — by ignition priming, by the starter, or by being driven. Leave your motor off and call Petrol in Diesel — that keeps it like that. Read on for three things: the effect petrol has inside a diesel motor, the clues of how far it has got, and the way to make sure you never do it again.
Petrol in a diesel: what does it do to the engine?
On its way through a motor, diesel has two jobs. Before it burns, it protects — and then it combusts. What stops the surfaces inside the high-pressure pump and the fuel injectors from grinding against one another is the diesel passing through them — they are designed to very fine tolerances.
The second task petrol does not do at all, and the first it does poorly. It's thinner than diesel and strips away the lubrication the fuel system hinges on, so a pump running on a petrol mixture 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 clattering comes from.
The shape of the trouble is clear once you put those together. It is circulation that does the harm, not contact. A tank with petrol in it is a fuel problem. Whatever a worn pump sheds travels on, carried by your fuel, into the fuel injectors downstream, which is why a pump that has worked on that petrol is where a mechanical fault starts.
How bad is petrol in a diesel? Four scenarios our technicians see in Priorslee
The best case there is: filled up, never started. At a forecourt, and really only there, the petrol is still limited to the tank — since everywhere else the car was driven to reach it. The task is emptying and rinsing on the spot.
A moment's running, or just the ignition on. Petrol has left the tank and got to the fuel filter and your lines, since the fuel system has been bled. Drain, flush, see to the fuel filter: still normally simple.
A few miles driven, and your pump has spent each of them working on thinned fuel. The work is that tank, the fuel lines, the filter and clean fuel through the entire system, and how hard your car was driven matters as much as how far. A school run to Priorslee Academy is one thing. Any miles on the M54, under a mile from Priorslee, means your engine working hard throughout, and a run to Wolverhampton, under 15 miles away, makes a very different job as well.
Driven until it complained. Clattering, a lumpy idle, smoke, a throttle that has gone soft. The fuel is not behaving like diesel any more, and your motor is telling you. Stop wherever you are — the verge on Everglade Road, a lay-by, a side street — and leave it there. Permanent damage is very uncommon when a car is pulled over early, and the fuel drain and flush that still come first deal with it.
Petrol in a diesel myths Priorslee people hear
"Top it up the rest of the way with diesel and it'll be fine" — a myth. It won't. Nothing is removed by topping up — you're left with a bigger tank, still the same mixture. The idea behind that guidance — that diesel fuel systems accept petrol by percentage — is wrong.
Myth: "A current diesel can cope with a bit of petrol." If anything, the opposite. Lubrication counts more on modern diesels, not less, because their fuel runs through finer parts at higher pressure.
One myth that catches drivers out: if it starts and drives, it must be unharmed. The driver of a petrol motor fed diesel normally stops, since it will not run, and the damage stops there. Feed petrol to a diesel and it generally starts, ticks over and pulls away like nothing happened — all the while its pump wears. Being able to run is not proof of being fine.
An outdated workaround for a distinct issue is behind this one. Myth: "Add some two-stroke oil and drive the car home." None of what petrol diluted is put back by it — and afterwards, the tank still contains that petrol.
The next start sends petrol back round your pump from the fuel lines and the fuel filter, where some of it ends up once your engine has run. That is why a DIY tank drain does not sort it — a myth. Besides, petrol emptied into a can by the road is genuinely dangerous.
Why petrol in a diesel happens so easily
No one does it on purpose, and it is seldom carelessness. The forecourt makes it easy: the petrol nozzle is the smaller of the two, and it slides into a diesel filler with almost no resistance, while a diesel nozzle generally won't go into a petrol motor at all. So the mistake runs one way.
It happens when routine and the vehicle stop matching. A new vehicle, a hire car or a courtesy car. Households running one of each, petrol and diesel. The pumps in a different order on a well-known forecourt. Rushing for a train outside Telford Central and fuelling up en route. Exactly the moment it occurs: after years of driving petrol, someone fills a diesel Volkswagen Golf for the first time. Your hand does what it has always done once you add rain, a phone call or a back seat full of children.
Priorslee drivers: how to avoid petrol in a diesel next time
- The label is what counts, and so check the pump instead of the colour: in the UK unleaded handles are normally green and diesel black, yet not on each forecourt.
- Plenty of motors state the fuel inside your filler flap or on the cap, and so check it on your first fill in a vehicle you do not know.
- Good intentions do less than a sticker or a fob in a bright colour on the diesel's key if a home has one of each. So mark it.
- Before the nozzle comes off the pump the first time you fuel a hired or new car, say "diesel" out loud. Daft, yes, yet it does the trick.
- Mistakes like this are straightforward to make whilst your mind is on something else, and so your phone goes away.
- Up to a point, a misfuel inhibitor helps: some diesels come with a filler built to reject a petrol nozzle, and aftermarket devices are available for the rest. Treat it as a backstop, and keep reading the petrol pump.
- Stop as soon as you realise. Less petrol inside that tank makes a weaker mix. It does not change what to do next, which is still not to crank it.
Priorslee: already put petrol in a diesel?
Then, there is only a short order of things. Leave it unstarted, with the ignition switched off too. Yet at the forecourt, at Shell or anywhere else? Ask the staff to help you roll the car clear of the petrol pump. Next, 0333 366 0103. We will ask what got in, about how much, and if it's been run.
If it was AdBlue instead of petrol, say so. That is a separate problem — corrosion and deposits rather than lost protection — and it has its own page for Priorslee.
One petrol in a diesel task around Priorslee costs more than another. Why?
Four different jobs sit behind the four situations above — which is why there is no fair single quote. Chiefly, the cost shifts with which situation you are in. Where your car is counts too, and whether a van can safely reach it, after the proportion of petrol to what that tank takes.
That's why we ask three questions before pricing rather than after: what got in, how much, and whether it's run. The answers turn a range into a straight figure.
About Priorslee
Priorslee is a suburban area in Shropshire, situated inland at an elevation of around 145 metres, with detached housing being the predominant type of accommodation. Priorslee lies approximately 14 miles from Wolverhampton and 127 miles from London, placing it within the wider West Midlands region. Priorslee is close to nearby places such as Stafford Park, Snedshill, and Hollinswood, and has a population of around 2767 residents. Priorslee forms a residential community with a mix of local amenities and services.
Across Shropshire and around Priorslee: fuel drain cover
Priorslee sits in the TF postcode area, and our teams that answer petrol in diesel calls there work the spots near it as well — Stafford Park, Snedshill and Hollinswood among them. Our engineers drain where the vehicle is — your own drive, a lay-by, a supermarket car park, a forecourt — so it never needs to come to us.
Still at the pump around Priorslee?
The best position there is, then — that's where you are. Keep it off. Ring.