Should You Worry? Petrol in a Diesel Car in Nantwich
Provided it has not been started, you can worry far less than you likely are. Petrol resting in a diesel tank does nothing to the motor till something pulls it through the fuel system — the ignition priming your pump, the starter, or driving on its own. So the fair answer to the first question anyone around Nantwich asks, "have I wrecked it?", is generally no. To keep the vehicle that way, phone Petrol in Diesel then leave the engine alone. What petrol really does to a diesel, how to judge how far it's travelled, and how to stop it from happening again: that's the rest of this page.
What petrol in a diesel does to the motor
On its way through an engine, diesel does two tasks. Before it ignites, it protects — and then it combusts. Built to extremely fine tolerances, the fuel injectors and the pump depend on your diesel flowing through them to keep their surfaces from wearing against one another.
The second job petrol doesn't do at all, and the first it does poorly. It is thinner than diesel and removes the lubrication the system hinges on, and so a pump running on a petrol mixture is a pump wearing itself. And petrol is made to resist igniting under compression, which is the opposite of what a diesel needs from its fuel. That's where the knocking comes from.
The shape of the issue is plain when you put those together. The damage is done by movement, not by contact. Petrol in the tank is a fuel problem. The beginning of a mechanical one is a pump that has been working on that petrol — and whatever a worn pump sheds travels on with the fuel to your injectors downstream.
Four situations our technicians see in Nantwich: how bad is petrol in a diesel?
Filled up, and never started: nothing beats it. Just the tank has petrol in it, and so the task is emptying that tank and purging the fuel system where your car stands. This situation can only truly happen on a forecourt: anywhere else, the vehicle got there by being driven.
A moment's running, or just the ignition on. Once primed, the fuel system has drawn petrol from your tank as far as your filter and the fuel lines. That is generally still an easy task — a drain, a flush, and the filter dealt with.
The pump has worked a couple of miles on weakened fuel — that is what driving the vehicle meant. The work is the tank, the lines, the filter and fresh fuel through the entire system, and how hard the car was driven matters as much as how far. Short trips, like the school run to Nantwich Primary Academy, are one thing. Very different a second time: a run to Stoke-on-Trent, under 15 miles away, or any miles on the M6, under 10 miles from Nantwich, where your engine kept working hard.
Driven till it protested. Knocking, a lumpy idle, smoke, a throttle that has gone soft. The fuel isn't acting like diesel any more, and your engine is saying so. Whether it is the verge on Beam Street, a lay-by or a side street, stop where you are then leave it. The fuel drain and flush still go first, and they deal with it: if a car is pulled over soon, lasting damage is very rare.
Stories Nantwich drivers hear about petrol in a diesel
"Top it up the rest of the way with diesel and it will be fine" — a myth. It will not. Nothing comes out when you top up — that tank just carries more of the same blend. That advice presumes a diesel fuel system handles petrol by percentage. It doesn't.
"Newer diesels can handle a little petrol" — a myth, and closer to the opposite. Protection counts more on newer diesels, not less, since their fuel passes through finer parts at higher pressure.
This is the one that catches motorists. Myth: "If it starts and drives, there is no damage done." A petrol motor fed diesel normally will not run, and so the motorist stops and the damage stops with them. Whilst the pump grinds, a diesel fed petrol normally starts, idles and drives away as if nothing has happened. A running engine doesn't mean fine.
An old workaround for a different problem lies behind this one. Myth: "Add some two-stroke oil and drive it home." What petrol has thinned stays weakened, and that petrol stays in your tank regardless.
"Drain it yourself and you are sorted" — a myth, since after it has been running some petrol sits in the filter and lines, waiting to go straight back through your pump at your next start. It is also truly dangerous to drain petrol into a can at the roadside.
Why petrol in a diesel happens so easily
A careless moment is rarely the cause, and no one means to do it. One way only, since of the nozzles: the narrower petrol one slides inside a diesel filler with almost no resistance, whereas the diesel one mostly will not fit a petrol car. That is how the forecourt makes it straightforward.
It takes place when habit and the vehicle stop matching. A car that is new to you — hired, on loan as a courtesy car, or just bought. Households running one of each, petrol and diesel. A familiar forecourt with the pumps in a different order. A rushed fill en route to the nearest station with a train to catch. Years of petrol motors behind you, a diesel Volkswagen Passat in front of you on the forecourt for its first tank — that is when. Throw in a back seat full of children, a phone call or rain, and habit takes over.
Nantwich drivers: how to prevent 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 usually green and diesel black, but not on each forecourt.
- In a vehicle you don't know, look inside the flap over the filler or at the cap before your first fill: plenty of cars print the fuel type there.
- One of each in the home? Mark your key to the diesel — a coloured fob, a sticker — because intending to remember isn't enough.
- Say it before you lift it. On your first fill in a new or hired car, say "diesel" aloud before you take the nozzle off the petrol pump. It sounds daft and it does the trick.
- While you are thinking about something else, this is an easy mistake to make — so tuck your phone away.
- Some diesels have a filler built to block a petrol nozzle, and devices you can add exist for vehicles without one. Such an inhibitor helps up to a point — as a safety net, not a reason to stop reading the petrol pump.
- Spotting it mid-fill? Stop at once. A weaker blend follows from less petrol in your tank, yet your next stage remains the same: do not crank it.
Nantwich: already put petrol in a diesel?
The order of things is brief, then. Don't switch your ignition on, and do not start it. The staff on the forecourt — whether at Morrisons itself or wherever you filled up — will usually help push it clear of the pump if you ask. Then phone 0333 366 0103 and tell us what was put in, roughly how much, and whether it's run.
If it was AdBlue rather than petrol, say so. That's a separate problem — corrosion and deposits rather than lost protection — and it has its own page for Nantwich.
Nantwich petrol in a diesel jobs: why one costs more than another
The four scenarios above are four separate jobs, so no single price for this would be fair. Which of them you are in is mostly what moves your cost. Next it is the share — how much petrol got in against how much the tank takes — and then where your car is and whether our van can get to it safely.
That's why our technicians ask three queries before costing rather than after: what went in, how much, and if it's run. Their answers are what turn a range into one firm number.
About Nantwich itself
Nantwich is a town in Cheshire, situated on the banks of the River Weaver, with a mix of old and new buildings reflecting its long history. Nantwich sits at an elevation of around 40 metres, near the villages of Acton and Butt Green, and is connected to nearby cities like Stoke-on-Trent. Nantwich has a population of approximately 17502 people, predominantly living in semi-detached houses. Nantwich is located in the North West region of England, about 147.9 miles from London.
Nantwich and Cheshire: where our fuel drain cover runs
Our teams answering petrol in diesel call-outs around Nantwich, in the CW postcode area, also work the spots near it, Snow Hill, Butt Green and Acton among them. The vehicle doesn't need to move to us: our engineers drain at a forecourt, in a supermarket car park, in a lay-by or on your own driveway.
Nantwich: still at the pump?
In that case, you couldn't be in a better position. Switched off it remains; then ring.