Should You Worry? Petrol in a Diesel Car in Milnrow
If it hasn't been started, worry far less than you probably are. Petrol resting in a diesel tank does nothing to your motor till something pulls it through the fuel system — your ignition priming the pump, your starter, or the drive itself. So the truthful answer to the first question everyone around Milnrow asks, "have I ruined it?", is generally no. Petrol in Diesel is who to phone, with the motor kept off, so it stays that way. What petrol actually does to a diesel, how to judge how far it's travelled, and how to keep it from happening again: that's the remainder of this page.
Inside the engine: what petrol in a diesel really does
Passing through a motor, diesel is doing two jobs at the same time. It lubricates to begin with, and only then does it burn. What stops the surfaces inside your high-pressure pump and the injectors from grinding against one another is the diesel passing through them — they are designed to extremely fine clearances.
Badly at the first, not at all at the second: that is petrol. A pump working on a petrol blend is wearing itself out, because petrol is thinner than diesel and strips out the lubrication the fuel system depends on. Petrol is also made to resist igniting under compression — the opposite of what a diesel wants from its fuel — and that is where the knocking starts.
Put those together and the shape of the trouble is clear. It is movement that does the damage, not contact. Where that petrol is only inside the tank, it is an issue of fuel, nothing more. After your pump has been working on that petrol, a mechanical issue has started: whatever is shed by a pump that is wearing is carried onward to your injectors with the fuel.
How bad is petrol in a diesel? Four situations we see in Milnrow
Fuelled up, not once started. The best case there is. On a forecourt, and genuinely only there, the petrol is still limited to that tank — since anywhere else your car was driven to reach it. The task is emptying and purging on the spot.
A brief spell of running, or just your ignition on. Your system has been primed, so petrol has left the tank and reached the fuel filter and the lines. Normally nothing more than emptying, flushing and seeing to your filter, so still straightforward.
A few miles driven, and your pump has spent every one of them labouring on diluted fuel. Tank, lines, filter, then fresh fuel run through the entire system: that is this work, and the way the vehicle was driven counts as much as the miles. Driving the kids to Milnrow Parish Church of England Primary School is one kind of trip. A run as far as Manchester, under 15 miles away, is a very different task. So is any mileage on the M62, under a mile from Milnrow, where the motor has been labouring hard throughout.
Driven until it complained. Knocking, a lumpy idle, smoke, a throttle that has gone soft. The motor is telling you the fuel is no longer acting like diesel. Whether it's the verge on Kiln Lane, a lay-by or a side street, stop where you are and leave it. A car pulled over early very seldom has long-term damage, as the fuel drain and the flush, which still go first, deal with it.
Stories Milnrow motorists hear about petrol in a diesel
"Top it up the rest of the way with diesel and it'll be fine" — a myth. It will not. Topping up removes nothing; it gives you a bigger tank of the same mix. That advice assumes a diesel fuel system tolerates petrol by percentage. It doesn't.
If anything, the opposite is true. Myth: "A modern diesel can cope with a bit of petrol." At higher pressure, through more precise parts: that's how a newer diesel handles its fuel, so the lubrication matters more, not less.
Myth: "If it starts and drives, there is no damage done." This is the one that fools motorists. Diesel in a petrol motor generally leaves a motor that will not run: the motorist stops, and so does the harm. A diesel fed petrol usually starts, ticks over and drives away as though nothing has happened, whilst your pump grinds. A running engine does not mean fine.
"A drop of two-stroke oil and drive it home" — a myth, borrowed from a fix from years ago, for a different problem. None of what petrol thinned is put back by it — and later, your tank still contains that petrol.
Myth: "Drain that tank yourself and you're sorted." Once your engine has been run, some of that petrol is no longer inside your tank: it is in the filter and your lines, and it goes straight back through the pump at your next start. It is also really hazardous to drain petrol into a can at the roadside.
Petrol in a diesel: how does it happen?
It's seldom carelessness, and nobody does it on purpose. One way only, because of the nozzles: the smaller petrol one slides inside a diesel filler with almost no resistance, while the diesel one mostly will not fit a petrol car. That's how the forecourt makes it straightforward.
When habit and your car stop matching, it occurs. Hire cars, courtesy cars, and cars that are new to you. One petrol and one diesel on the driveway of the same household. A forecourt you know, only with its pumps laid out differently. Filling up in a hurry on the way to Smithy Bridge, with a train to catch. Precisely the moment it happens: after years of driving petrol, a driver fills a diesel BMW 3 Series for the first time. With rain, a call arriving, or children to deal with, your hand just does what it always has.
Next time you fill up around Milnrow: preventing petrol in a diesel
- Read the petrol pump, not the colour. In the UK unleaded handles are usually green and diesel black, yet not on each forecourt. The label is what counts.
- Many cars state the fuel inside your filler flap or on the cap, so check there on the first fill in a car you do not know.
- Label your key. In a house with one of each, a coloured fob or a sticker on your diesel's key does more than any amount of intending to remember.
- Say it before you lift it. On the first fill in a new or hired car, say "diesel" out loud before you lift the nozzle off the pump. It seems daft and it does the trick.
- Whilst you're thinking about something else, this is an easy mistake to make — so tuck the phone away.
- A misfuel inhibitor helps, up to a point. Some diesels come with a filler designed to refuse a petrol nozzle, and add-on devices are available for cars without one. They are a backstop, not a reason to stop reading the pump.
- Less petrol makes a thinner mix, so stop the moment you notice — though remembering that the next step is unchanged. It is still not to crank it.
Already put petrol in a diesel in Milnrow?
Then the order of things is brief. Starting it is out, and so is turning on your ignition. The attendants on the forecourt — whether at Esso itself or wherever you filled up — will normally help push it clear of the petrol pump if you ask. Then call 0333 366 0103 and tell us what got in, roughly how much, and if it's run.
If it was AdBlue and not petrol, say so. That's a different issue — corrosion and deposits and not lost protection — and it has its own page for Milnrow.
Milnrow petrol in a diesel tasks: why one costs more than another
There's no honest single quote for this, since the four scenarios above are four separate jobs. The scenario itself does most of the work of moving your cost. Two things come after that: the petrol that went in as a share of what the tank holds, then the spot the vehicle is in and whether a technician can reach it safely.
Three questions come first, before quoting, rather than after — what went in, how much, has it run — and this is the reason. Given the answers, you get a straight figure instead of a range.
About Milnrow itself
Milnrow is a town in Greater Manchester, situated on the riverside in the North West of England, with an elevation of 144 metres. Milnrow lies approximately 10.6 miles from Manchester and 167.6 miles from London, surrounded by nearby places such as Firgrove, Lady House, and Belfield. Milnrow has a population of around 13,732 people, predominantly living in semi-detached housing. Milnrow's setting has contributed to its development as a residential town with a strong sense of community.
Across Greater Manchester and around Milnrow: fuel drain cover
Our vans answering petrol in diesel calls in Milnrow, in the OL postcode area, equally work the locations near it, Firgrove, Lady House and Belfield included. No need to move your vehicle to us. Forecourts, supermarket car parks, lay-bys and your own drive are all places where we work.
Still at the pump around Milnrow?
Nothing beats it: that's where you now are. Keep it off. Call.