Should You Worry? Petrol in a Diesel Car in Ardwick
Provided it has not been started, worry far less than you likely are. Until the ignition primes your pump, your starter cranks, or the car is driven, petrol in a diesel tank just rests there and does no harm. Which means the truthful reply to the first Ardwick query — "have I wrecked it?" — usually no. To leave the car that way, call Petrol in Diesel then leave your engine switched off. Further down, you will find what petrol actually does inside a diesel, how far it may have gone, and how to stop it happening to you a second time.
Inside your engine: what petrol in a diesel does
Diesel has two jobs on its way through an engine. Lubricating comes before burning; it does both. Built to very fine tolerances, the fuel injectors and the pump depend on the diesel flowing through them to keep their surfaces from wearing against one another.
Poorly at the first, not at all at the second: that's petrol. It's thinner than diesel and takes away the protection your fuel system hinges on, and 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 knocking comes from.
Put those together and the shape of the problem is plain. The damage is done by circulation, not by contact. A tank with petrol in it is a fuel fault. The beginning of a mechanical problem is a pump that has been labouring on that petrol — and whatever a worn pump sheds moves on with your fuel to the injectors downstream.
Four scenarios our technicians see in Ardwick: how serious is petrol in a diesel?
Filled but not once started — as good as it gets. Just your tank has petrol in it, and so the job is clearing that tank and rinsing your system where your car sits. This scenario can only truly occur at a forecourt: anywhere else, the vehicle got there by being driven.
A moment's running, or merely the ignition on. Once primed, the system has pulled petrol out of your tank as far as the fuel filter and the lines. Drain, flush, see to the filter: still usually simple.
Your pump has spent a few miles on weakened fuel — that is what driving it does. The work is that tank, your lines, the filter and clean fuel through the whole circuit, and how hard the vehicle was driven counts as much as how far. On the school run to Co-op Academy Medlock, the mileage is short. A run as far as Manchester, under 3 miles away, is a very different task. So is any distance on the Mancunian Way, under a mile from Ardwick, where the engine has been labouring hard throughout.
It protested, and only then stopped: smoke, clattering, a throttle gone soft, an idle gone ragged. The engine is telling you the fuel is no longer behaving like diesel. Whether it's the verge on Higher Ardwick, a lay-by or a side street, stop there then leave it. The fuel drain and flush-through still come first, and they take care of it: if a vehicle is stopped early, lasting damage is very uncommon.
Ardwick 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." A bigger tank of the same mixture is all it gives, because topping up takes out nothing. That advice assumes a diesel fuel system tolerates petrol by percentage. It doesn't.
If anything, the opposite holds. Myth: "A modern diesel can cope with a bit of petrol." Protection counts more on newer diesels, not less, since their fuel passes through smaller components at higher pressure.
"It starts, it drives, and so no harm done" — the myth that catches more drivers than any other. Any petrol engine fed diesel normally won't run, and so the driver stops and the harm stops with them. While the pump wears, a diesel fed petrol usually starts, idles and drives away as if nothing has happened. Running is not the same as fine.
"A drop of two-stroke oil and drive it home" — a myth, borrowed from a fix from years ago, for a distinct fault. It does not put back what petrol has diluted, and that petrol is still inside that tank afterwards.
"Drain it yourself and you're sorted" — a myth, since after it's been running some petrol sits in the filter and lines, ready to go straight back through your pump at your next start. Besides, petrol emptied into a can by the road is truly risky.
How it happens: petrol in a diesel
On purpose? Never. Through carelessness? Seldom, if ever. The forecourt makes it simple: the petrol nozzle is the narrower 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.
It takes place when habit and your car stop matching. A new motor, a hire car or a courtesy car. Two vehicles on one driveway, one petrol, one diesel. A forecourt you know, but with its pumps arranged differently. A train to catch, and a hurried fill on the way to the nearest station. Exactly the moment it takes place: after years of driving petrol, someone fills a diesel Peugeot 308 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 kids.
How to prevent petrol in a diesel on your next fill-up in Ardwick
- The label is what matters, and so read 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 do not know, look inside the flap over the filler or at the cap before the first fill: plenty of vehicles print the fuel type there.
- One of each in the household? Mark your key to your diesel — a bright fob, a sticker — since intending to remember isn't enough.
- Before the nozzle comes off the petrol pump the first time you fill a hired or new motor, say "diesel" out loud. Daft, yes, but it works.
- While you're thinking about something else, this is an easy mistake to make — so tuck the phone away.
- Some diesels come with 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 backstop, not a reason to stop checking the petrol pump.
- Less petrol means a weaker mixture, and so stop as soon as you realise — though remembering that the next stage is unchanged. It's still not to fire it up.
Put petrol in a diesel in Ardwick already?
In that case, there is just a short order of things. Starting it is out, and so is turning on the ignition. Ask the staff to help you push it clear of the pump if you're still at the forecourt, whether that's Esso or anywhere else. What went in, about how much, and if it's run: tell us those when you call 0333 366 0103.
AdBlue, not petrol? Then say so. Corrosion and deposits, not lost protection, make it a different fault — Ardwick has a page all for it.
One petrol in a diesel task in Ardwick costs more than another. Why?
There's no honest single price for this, since the four situations above are four different tasks. Which of them you are in is mostly what shifts the cost. Two things come after that: the petrol that was put in as a share of what your tank takes, then the spot the vehicle is in and whether a technician can reach it safely.
What went in, how much, and if it's run — three questions our engineers ask before costing, not after, for precisely that reason. A range becomes a straight figure when the replies are in.
About Ardwick itself
Ardwick is a suburban area in Greater Manchester, situated near the River Medlock and close to the city centre of Manchester. Ardwick is characterized by its terraced housing and lies at an elevation of around 45 metres, with nearby neighbourhoods including Brunswick and Ancoats. Ardwick is also close to the University of Manchester and benefits from its proximity to the city's amenities. Ardwick has a population of approximately 3938 residents.
Fuel drain cover in Ardwick and across Greater Manchester
Our teams answering petrol in diesel jobs around Ardwick, in the M postcode area, equally work the locations around it, Brunswick, University and Ancoats among them. A forecourt, a supermarket car park, a lay-by or your own drive are all places our engineers drain, and your car doesn't need to come to us.
At the pump in Ardwick, still?
Then, you could not be in a better position. Keep the car turned off, then ring.