How Worried Should You Be? Petrol in a Diesel Car in Danesmoor
Likely less than you are now — provided no one has started it. "Have I ruined it?" is the first question anyone in Danesmoor asks, and the honest answer is usually no, because petrol resting in a diesel tank hurts nothing till it's drawn through the fuel system — by ignition priming, by your starter, or by being driven. Leave your engine off and phone Petrol in Diesel — that keeps it that way. Read on for three things: the effect petrol has inside a diesel engine, the signs of how far it has spread, and ways to make sure you never do it again.
Petrol in a diesel: what does it do to the motor?
On its way through a motor, diesel has two tasks. Oiling comes before burning; it does both. What stops the surfaces inside your high-pressure pump and the fuel injectors from wearing down against each other is the diesel flowing through them — they are made to very fine clearances.
Petrol handles the first task badly and the second not at all. The rattling comes from petrol being designed not to ignite when compressed, which is precisely the opposite of what a diesel needs. On top of that it is thinner than diesel, it strips away the protection the system rests on, and any pump running on that mix is wearing itself.
Together, those make the shape of the problem clear. Contact does not do the harm — movement does. Any tank with petrol in it is a fuel fault. Whatever a worn pump sheds travels on, borne by the fuel, into your injectors further along, which is why a pump that has been working on the petrol is where a mechanical issue begins.
Petrol in a diesel around Danesmoor: how bad is it? Four situations
Filled but never started — as good as it gets. That petrol is in the tank and only the tank, and the job is a drain and a flush where your car stands. This is the one scenario that can only really occur on a forecourt, because anywhere else your car has been driven to get there.
Ignition on, or started for a second. The system has been primed, so petrol has left the tank and reached your filter and the fuel lines. Drain, flush, see to the filter: still usually easy.
Driven a couple of miles. Now your pump has spent these miles running on weakened fuel. Tank, lines, filter, then fresh fuel put through the whole system: that is this work, and the way the car was driven matters as much as the distance. Short trips, like the school run to Sharley Park Community Primary School, are one matter. Any mileage on the M1, under 5 miles from Danesmoor, means your engine working hard throughout, and a run to Sheffield, under 25 miles away, is a very different job as well.
Driven until it complained. Rattling, a lumpy idle, smoke, a throttle that has gone soft. What you are hearing is your engine reporting fuel that no longer acts like diesel. Leave it where it stops: a lay-by, a quiet street, the verge on Pilsley Road. What comes first is still the fuel drain and flush-through, and that deals with it, with permanent damage very uncommon when a vehicle is stopped early.
What Danesmoor drivers get told about petrol in a diesel — and the myths in it
False: topping up to full with diesel makes it fine. It does not. A bigger tank of the same mixture is all you get, because topping up takes out nothing. Percentage isn't how a diesel fuel system tolerates petrol, whatever that guidance presumes.
If anything, the reverse holds. Myth: "A modern diesel can cope with a bit of petrol." Smaller parts and higher pressure are the way a current diesel runs its fuel, and that makes the protection matter more, not less.
Myth: "If it starts and drives, there is no damage done." This is the one that catches people. A petrol engine fed diesel generally 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 though nothing has happened. Fine and running aren't the same thing.
Myth: "Add some two-stroke oil and drive the vehicle home." It's an old fix for a separate problem. What petrol has diluted stays thinned, and the petrol remains inside your tank anyway.
If the motor has run, part of the petrol sits in the fuel filter and the fuel lines, not that tank — and your next start pulls it right back through your pump. So the myth "drain the tank yourself and you are sorted" doesn't hold. Emptying petrol into a can by the roadside is also truly risky.
How it happens: petrol in a diesel
It's seldom carelessness, and no one does it on purpose. The forecourt makes it easy: the petrol nozzle is the slimmer of the two, and it slides into a diesel filler with almost no resistance, while a diesel nozzle generally will not go into a petrol motor at all. So the error runs one way.
The moment habit stops matching your car is the moment it occurs. Hire cars, courtesy cars, and vehicles that are new to you. One petrol and one diesel on the driveway of the same household. Your usual forecourt, its pumps suddenly in a different order. Racing for a train outside Alfreton and fuelling up en route. Exactly the moment it occurs: after years of driving petrol, a driver fills a diesel Volkswagen Golf for the first time. Throw in rain, a phone call or a back seat full of children, and your hand does what it has always done.
Next time you fill up around Danesmoor: preventing petrol in a diesel
- The label is what counts, and so read the pump rather than the colour: in the UK unleaded handles are normally green and diesel black, yet not on every forecourt.
- The first fill in an unfamiliar motor is the time to check your filler flap — inside it, or on the cap, many motors state the fuel to use.
- Good intentions count for less than a sticker or a fob in a vivid colour on your diesel's key when a home has one of each. So label it.
- Before the nozzle comes off the petrol pump the first time you fill a hired or new car, say "diesel" aloud. Silly, perhaps, yet it does the trick.
- Mistakes like this are simple to make whilst your mind is on something else, so your phone goes away.
- Some diesels have a filler designed to reject 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 pump.
- The moment you realise, stop: less petrol in the tank makes a weaker mix. What to do next doesn't change, though — still do not fire it up.
Petrol already in a diesel in Danesmoor? Start here
The order of things is short, then. Never start the vehicle, and don't turn the ignition on. If you are still on the forecourt — Tesco or anywhere else — ask the attendants to help you push the car clear of the pump. Then phone 0333 366 0103 and tell us what went in, roughly how much, and if it's run.
Say so if it was AdBlue rather than petrol: it's a different issue, with its own page for Danesmoor, because AdBlue brings corrosion and deposits instead of lost lubrication.
What makes one Danesmoor petrol in a diesel job cost more than the next
There's no honest single price for this, because the four scenarios above are four different tasks. What moves your cost is chiefly which of them you're in. Where the vehicle is matters too, and whether a technician can safely reach it, after the share of petrol to what that tank takes.
Three questions come first, before any quote, rather than after — what was put in, how much, has it run — and that is the reason. Given the replies, there is a straight figure instead of a range.
About Danesmoor itself
Danesmoor is a suburban area in Derbyshire, situated near the River Rother and characterised by semi-detached housing. Danesmoor sits at an elevation of 132 metres, approximately 15 miles from Sheffield and close to nearby places such as Egstow and Clay Cross. Danesmoor is located in the East Midlands region, about 126 miles north of London. Danesmoor has a population of around 3522 residents.
Fuel drain cover around Danesmoor and across Derbyshire
The vans answering petrol in diesel calls in Danesmoor, in the S postcode area, also work the spots around it, Egstow, Clay Cross and Parkhouse Green among them. You need not bring your car to us. Forecourts, supermarket car parks, lay-bys and your own drive are all places where we work.
At the pump around Danesmoor, still?
Then you are in the best spot there can be. Leave the car turned off, and ring.