Winnington: Petrol in a Diesel Car? How Worried to Be
Likely less than you are now — as long as no one has started the vehicle. Till your ignition primes the pump, your starter cranks, or the vehicle is driven, petrol in a diesel tank simply rests there and does no harm. Which means the honest reply to the first Winnington question — "have I wrecked it?" — normally no. To keep the car that way, phone Petrol in Diesel and leave your motor alone. The remainder of this page sets out what petrol actually does to a diesel, how to tell how far it has got, and how to make sure it does not happen to you a second time.
The engine and petrol in a diesel: what happens
Two jobs fall to diesel on its journey through a motor. Before it combusts, it protects — then it ignites. The high-pressure fuel pump and the injectors are built to extremely fine tolerances, and the diesel passing through them is what keeps those surfaces from grinding against one another.
The second job petrol doesn't do at all, and the first it does badly. It's thinner than diesel and removes the lubrication the system rests on, so a pump running on a petrol blend is a pump wearing itself. And petrol is designed to resist igniting under compression, which is the opposite of what a diesel needs from its fuel. That is where the rattling comes from.
Combined, those make the shape of the problem plain. Not contact but movement is what causes the damage. Where that petrol is only in that tank, it is a problem of fuel, nothing more. Once your pump has been labouring on that petrol, a mechanical fault has started: whatever is shed by a pump that is grinding travels downstream to the injectors with your fuel.
Four scenarios our engineers see in Winnington: how serious is petrol in a diesel?
Fuelled but not once started — as good as it gets. The petrol is inside the tank and only your tank, and the task is a drain and a flush where the vehicle sits. This is the one situation that can only truly happen at a forecourt, because anywhere else the vehicle has been driven to get there.
Ignition on, or started for a second. Petrol has come out of that tank and got to the fuel filter and your lines, because the system has been bled. Usually little more than emptying, purging and seeing to the fuel filter, and so still easy.
Driven a few miles. Now the pump has spent these miles working on thinned fuel. Tank, lines, filter, then clean fuel put through the entire system: that's the work, and the way your car was driven matters as much as the mileage. On the school run to Winnington Park Community Primary and Nursery School, the distance is small. A run as far as Chester, under 25 miles away, is a very different job. So is any miles on the M6, under 10 miles from Winnington, where your engine has been working hard throughout.
It protested, and only then stopped: smoke, rattling, a throttle gone soft, an idle gone ragged. The motor is telling you your fuel is no longer behaving like diesel. Whether it's the verge on Moreton Street, a lay-by or a side road, stop there then leave it. A car pulled over quickly very seldom has long-term damage, since the drain and the flush, which still come first, deal with it.
What Winnington drivers get told about petrol in a diesel — and the myths in it
Myth: "Fill it the rest of the way with diesel and it will be fine." It will not. Topping up removes nothing; it gives you a fuller tank of the same mix. Percentage isn't how a diesel fuel system tolerates petrol, whatever that advice supposes.
"Modern diesels can handle a little petrol" — a myth, and nearer the reverse. Lubrication counts more on newer diesels, not less, since their fuel passes through more precise components at higher pressure.
"It starts, it drives, so there is no harm" — the myth that catches more people than any other. Diesel in a petrol motor usually leaves a motor that won't run: the driver stops, and so does the harm. A diesel fed petrol generally starts, idles and drives away as if nothing has happened, whilst your pump wears. Running isn't the same as fine.
Myth: a two-stroke additive makes it safe to drive home. It was an old workaround, meant for another problem. What petrol has diluted stays weakened, and that petrol stays inside your tank regardless.
If the engine has run, part of that petrol sits in your filter and the lines, not the tank — and your next start pulls it right back through your pump. So the myth "drain that tank yourself and you're sorted" doesn't stand up. Also, a can of petrol filled by the kerbside is truly risky.
Why petrol in a diesel occurs at all
On purpose? Never. Through carelessness? Rarely, if ever. 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, while a diesel nozzle mostly won't go into a petrol car at all. So the error runs one way.
Routine and the vehicle getting out of step is when it occurs. Courtesy car, hire car, or a vehicle that's brand new. One petrol and one diesel on the drive of the same household. The pumps in a different order on a familiar forecourt. Fuelling up in a rush on the way to Greenbank, with a train to catch. Years of petrol cars behind you, a diesel Renault Megane in front of you on the forecourt for its first tank — that is when. Throw in rain, a phone call or a back seat full of children, and the hand does what it has always done.
Winnington drivers: how to prevent petrol in a diesel next time
- Not every forecourt in the UK keeps to green for unleaded and black for diesel, though most generally do. Read the petrol pump's label; the colour is just a clue.
- Plenty of vehicles state the fuel inside your filler flap or on the cap, and so check there on your first fill in a motor you do not know.
- One of each in the house? Mark the key to the diesel — a coloured fob, a sticker — because intending to remember isn't enough.
- "Diesel", aloud, before you lift the nozzle — every time a new or hired car gets its first tank. It sounds silly. It does the trick.
- Mistakes like this are straightforward to make whilst your mind is on something else, and so the phone goes away.
- Up to a point, a misfuel inhibitor helps: some diesels have a filler built to block a petrol nozzle, and aftermarket devices are available for the remainder. Treat it as a backstop, then keep checking the pump.
- Stop as soon as you realise. Less petrol in your tank means a weaker mix. It does not change what to do next, which is still not to crank it.
Petrol already in a diesel around Winnington? Start here
In that case, there's just a short order of things. Leave it unstarted, with the ignition off too. Yet on the forecourt, at BP or anywhere else? Ask the attendants to help you roll the vehicle away from the petrol pump. Then ring 0333 366 0103 and tell us what went in, about how much, and if it's run.
AdBlue, not petrol? Then tell us. Corrosion and deposits, not lost protection, make it a different fault — Winnington has a page just for it.
What makes one Winnington petrol in a diesel task cost more than the next
There is no fair single quote for this, because the four scenarios above are four separate tasks. Which of them you are in is mostly what moves the cost. Two things follow that: the petrol that was put in as a share of what the tank holds, then the spot your car is in and whether a technician can reach it safely.
Before any quote, not after, come three queries: the fuel that was put in, the amount, and if it has run. That is why. Those answers turn a range into a straight figure.
About Winnington, briefly
Winnington is a suburban area in Cheshire, situated inland at an elevation of 38 metres, with semi-detached housing being the predominant type of accommodation. Winnington lies approximately 15.8 miles from Chester and 157.9 miles from London, placing it in a relatively central location within the North West region. Winnington is surrounded by nearby places such as Greenbank, Northwich, and Hartfordbeach, and has a population of around 4781 residents. Winnington's setting is characterized by its proximity to these local communities and its inland location.
Across Cheshire and in Winnington: fuel drain cover
Petrol in diesel jobs in Winnington — part of the CW postcode area — go to vans that likewise cover the places about it, Greenbank, Northwich and Hartfordbeach included. No need to move your car to us. Forecourts, supermarket car parks, lay-bys and your own drive are all locations we drain.
Still at the petrol pump around Winnington?
Then you're in the best place there is. Keep it off. Phone.