Should You Worry? Petrol in a Diesel Car in Forest Green
Not started? Then less anxious than you probably feel. Petrol sitting in a diesel tank does nothing to the motor till something draws it through your fuel system — your ignition priming your pump, your starter, or driving on its own. So the truthful answer to the first question everyone around Forest Green asks, "have I wrecked it?", is normally no. To leave the vehicle like that, phone Petrol in Diesel then leave your engine switched off. The rest of this page covers what petrol really does to a diesel, how to judge how far it has got, and how to make sure it doesn't happen to you a second time.
Inside your engine: what petrol in a diesel does
On its way through a motor, diesel has two tasks. Lubricating comes before burning; it does both. The high-pressure fuel pump and the fuel injectors are built to very fine gaps, and your diesel passing through them is what stops those surfaces from wearing against each other.
Badly at the first, not at all at the second: that is petrol. The rattling comes from petrol being made not to ignite when compressed, which is precisely the reverse of what a diesel needs. On top of that it is runnier than diesel, it strips out the protection your system depends on, and any pump working on such a blend is wearing itself.
Combined, those make the shape of the problem clear. It is movement that does the harm, not contact. Where the petrol is only in that tank, it is a fault of fuel, nothing more. Whatever a worn pump sheds goes on, carried by the fuel, into your injectors downstream, which is why a pump that has been working on the petrol is where a mechanical problem begins.
Four scenarios our technicians see in Forest Green: how serious is petrol in a diesel?
Filled up, never started. The best case there is. The petrol is inside the tank and only that tank, and the task is a drain and a flush where the vehicle sits. This is the one situation that can only really occur at a forecourt, since anywhere else the car has been driven to get there.
A brief spell of running, or merely your ignition on. Petrol has come out of that tank and got to the fuel filter and the lines, since the fuel system has been bled. Usually little more than clearing, flushing and seeing to your filter, and so still straightforward.
Driven a couple of miles. Now your pump has spent these miles labouring on diluted fuel. How hard the vehicle was driven matters as much as how far, and the work covers your tank, the lines, the filter and clean fuel through the whole circuit. On the school run to Nailsworth Church of England Primary School, the distance is small. Any distance on the M5, under 10 miles from Forest Green, means your engine working hard throughout, and a run to Gloucester, under 15 miles away, is a very different job as well.
Rattling, a lumpy idle, smoke, a throttle gone soft: driven until it complained. The motor is telling you the fuel is no longer behaving like diesel. Whether it's the verge on Jubilee Road, a lay-by or a side road, stop where you are then leave it. The fuel drain and flush-through still come first, and they take care of it: if a car is stopped soon, long-term damage is very uncommon.
Myths Forest Green drivers hear about petrol in a diesel
Myth: "Fill it the rest of the way with diesel and it'll be fine." It will not. Nothing is removed by topping up — you're left with a fuller tank, still the same mixture. That guidance assumes a diesel fuel system tolerates petrol by percentage. It does not.
"Current diesels can handle a little petrol" — a myth, and nearer the reverse. Lubrication matters more on current diesels, not less, since their fuel passes through smaller components at higher pressure.
This is the one that fools motorists. Myth: "If it starts and drives, there is no damage done." The motorist of a petrol engine fed diesel normally has no choice but to stop, since it will not run, and the harm stops with them. A diesel fed petrol normally starts, ticks over and drives away as if nothing has happened, while the pump grinds. Being able to run is not the same as being fine.
Myth: "Add some two-stroke oil and drive the vehicle home." It's an old workaround for a distinct problem. What petrol has diluted remains thinned, and the petrol stays inside the tank regardless.
If the motor has been run, part of the petrol is in the fuel filter and your lines, not the tank — and your next start sends it right back through the pump. So the myth "drain your tank yourself and you are sorted" does not stand up. Also, a can of petrol filled at the kerbside is truly risky.
Petrol in a diesel: how does it take place?
Nobody does it on purpose, and it's rarely carelessness. The forecourt makes it easy: the petrol nozzle is the smaller 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 motor at all. So the error runs one way.
The moment habit stops matching your car is the moment it takes place. Courtesy car, hire car, or a vehicle that is new. One petrol and one diesel on the driveway of the same household. Your usual forecourt, its pumps suddenly in a different order. A train to catch, and a rushed fill on the way to Stroud. The first fill-up in a diesel Volkswagen Golf after years of driving petrol is exactly the moment it takes place. The hand repeats what it has always done once you add rain, a phone call or a back seat full of kids.
Forest Green people: how to avoid petrol in a diesel next time
- Check the petrol pump, not the colour. In the UK unleaded handles are generally green and diesel black, yet not on each forecourt. The label is what counts.
- Inspect the filler flap. Many cars state the fuel type inside the flap or on the cap. Look at it on the first fill in a car you do not know.
- One of each in the home? Mark your key to your diesel — a bright fob, a sticker — since meaning to remember isn't enough.
- Before the nozzle leaves the petrol pump the first time you fuel a hired or new car, say "diesel" aloud. Silly, perhaps, but it works.
- Tuck your phone away. This is an easy mistake to make while you are thinking about something else.
- Up to a point, a misfuel inhibitor helps: some diesels come with a filler designed to reject a petrol nozzle, and add-on devices are available for the rest. Treat it as a backstop, then keep checking the pump.
- Spotting it halfway? Stop there and then. A thinner blend results from less petrol inside your tank, but the next step stays the same: don't fire it up.
Petrol already in a diesel around Forest Green? Start here
Short and simple, then, is the order of things. Never start the car, and don't switch your ignition on. The attendants on the forecourt — whether at Shell itself or wherever you filled up — will normally help push it clear of the pump if you ask. Then call 0333 366 0103 and tell us what went in, about how much, and whether it has run.
If it was AdBlue instead of petrol, say so. That is a separate issue — corrosion and deposits and not lost protection — and it has its own page for Forest Green.
Forest Green petrol in a diesel tasks: why one costs more than another
An honest single quote doesn't exist here: four situations, four separate jobs. Which of them you're in is chiefly what moves the cost. Beyond that it is the proportion — how much petrol went in against how much your tank takes — and then where the vehicle is and whether a van can get to it safely.
Three queries come first, before quoting, rather than after — what got in, how much, has it run — and that is the reason. A range becomes a straight figure once the replies are in.
About Forest Green and where it is
Forest Green is a suburban area in Gloucestershire, situated on the riverside at an elevation of 127 metres. Forest Green lies near the city of Gloucester, approximately 11.5 miles away, and is also close to nearby places such as Windsoredge and Newmarket. Forest Green has a population of around 3890 people and is characterised by predominantly semi-detached housing. Forest Green is located in the South West region of England, about 91.1 miles from London.
Forest Green and Gloucestershire: where our fuel drain cover reaches
Petrol in diesel jobs around Forest Green — part of the GL postcode area — go to teams that also cover the spots round it, Windsoredge, Newmarket and Worley among them. We drain where your vehicle is — your own drive, a lay-by, a supermarket car park, a forecourt — so it does not have to come to us.
Forest Green: still at the petrol pump?
Then you are in the best position there is. Turned off it stays; then ring.