Should You Worry? Petrol in a Diesel Car in Whitehill
If it has not been started, you can worry less than you probably are. Petrol resting in a diesel tank does nothing to your motor until something pulls it through the system — your ignition priming your pump, your starter, or the drive itself. So the honest answer to the first question everyone around Whitehill asks, "have I wrecked it?", is normally no. Petrol in Diesel is who to phone, with the engine kept off, and so it remains that way. What petrol really does to a diesel, how to gauge how far it's gone, and how to stop it from happening again: that's the rest of this page.
What petrol in a diesel does to the motor
Diesel has two tasks on its way through an engine. It burns, and before it ignites it protects. Designed to very fine tolerances, your injectors and the pump rely on the diesel moving through them to stop their surfaces wearing against one another.
Petrol does the first task badly and the second not at all. The clattering comes from petrol being made not to ignite when compressed, which is exactly the opposite of what a diesel needs. On top of that it is runnier than diesel, it strips out the lubrication the fuel system depends on, and any pump working on that mix is wearing itself.
The shape of the trouble is clear when you put those together. Contact doesn't do the harm — circulation does. Where that petrol is only inside that tank, it's a problem of fuel, nothing more. After your pump has been labouring on that petrol, a mechanical problem has begun: whatever is shed by a pump that is grinding travels onward to your injectors with your fuel.
Four situations our technicians see around Whitehill: how bad is petrol in a diesel?
Fuelled but never started — the best it gets. Being on a forecourt is what makes this possible: elsewhere, your car has been driven there to begin with. With that petrol held inside the tank alone, it is emptied and cleaned right where it stands, and nothing more is needed.
A brief spell of running, or merely your ignition on. Once primed, your system has drawn petrol out of your tank as far as your filter and the lines. Still usually simple: drain, flush, and the fuel filter seen to.
Those few miles on the road were the pump running on fuel diluted by petrol throughout. Mileage is only half of it; how hard it was driven counts equally. Either way the work runs to the tank, your lines, your filter and clean fuel through the entire system. The school run to Dove Bank Primary School is one thing. Getting as far as Stoke-on-Trent, under 10 miles away, makes a very different task — as does any distance on the M6, under 5 miles from Whitehill, with the motor working hard the whole time.
Rattling, a lumpy idle, smoke, a throttle gone soft: driven until it complained. The motor is telling you the fuel is no longer acting like diesel. Leave it wherever it has stopped: a lay-by, a side street, the verge on Magpie Crescent. What goes first is still the fuel drain and flush, and that sorts it out, with permanent damage very uncommon if a vehicle is pulled over quickly.
Stories Whitehill motorists 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 comes out when you top up — that tank simply holds more of the same blend. A diesel fuel system does not accept petrol by percentage in the way that guidance supposes.
"Modern diesels can handle a little petrol" — a myth, and closer to the reverse. At higher pressure, through smaller parts: that's how a modern diesel moves its fuel, so the protection counts more, not less.
This is the one that fools people. Myth: "If it starts and drives, there is no damage done." The motorist of a petrol engine fed diesel usually stops, since it will not run, and the damage stops with them. While the pump grinds, a diesel fed petrol usually starts, ticks over and drives away as if nothing has happened. Running is not the same as fine.
An outdated workaround for a different problem lies behind this one. Myth: "Add some two-stroke oil and drive the vehicle home." None of what petrol weakened is put back by it — and later, the tank still contains that petrol.
Once the motor has run, part of that petrol is in the fuel filter and the fuel lines, not the tank — and the next start pulls it straight back through your pump. So the myth "drain that tank yourself and you are sorted" doesn't stand up. Clearing petrol into a can by the kerbside is also truly risky.
Petrol in a diesel: how does it happen?
It is rarely carelessness, and nobody does it on purpose. One way only, since of the nozzles: the slimmer petrol one slips inside a diesel filler with almost no resistance, whereas the diesel one mostly will not fit a petrol motor. That is how the forecourt makes it easy.
When routine and the car stop matching, it happens. Any vehicle that's new to you — hired, on loan as a courtesy car, or brand new. Two motors on one drive, one petrol, one diesel. A forecourt you know, only with its pumps arranged differently. A hurried fill on the way to Kidsgrove with a train to catch. The first fill-up in a diesel Renault Megane after years of driving petrol is exactly the moment it happens. Add a back seat full of children, a phone call or rain, and the hand takes over.
Next time you fill up around Whitehill: avoiding petrol in a diesel
- The label is what matters, so read the pump instead of the colour: in the UK unleaded handles are normally green and diesel black, but not on every 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 cars state the fuel there.
- Mark the key. In a house with one of each, a coloured fob or a sticker on the diesel's key does more than any amount of intending to remember.
- Before the nozzle leaves the pump the first time you fill a hired or new car, say "diesel" aloud. Daft, perhaps, but it works.
- Mistakes like this are simple to make whilst your mind is on something else, and so your phone goes away.
- A misfuel inhibitor helps, up to a point. Some diesels have a filler built to reject a petrol nozzle, and add-on devices are available for vehicles without one. They are a safety net, not a reason to stop checking the pump.
- The moment you notice, stop: less petrol in that tank means a weaker blend. What to do next does not change, though — still don't fire it up.
Put petrol in a diesel around Whitehill already?
Short and simple, then, is the order of things. Do not crank it, and don't switch the ignition on. The staff on the forecourt — whether at Tesco itself or wherever you filled up — will normally help push it clear of the petrol pump if you ask. What was put in, about how much, and whether it has run: tell us that when you call 0333 366 0103.
Say so if it was AdBlue rather than petrol: it's a different problem, with its own page for Whitehill, because AdBlue brings corrosion and deposits instead of lost protection.
What makes one Whitehill petrol in a diesel task cost more than the next
A fair single price doesn't exist here: four situations, four separate jobs. The situation itself does most of the work of moving your cost. Where the vehicle is counts too, and whether a technician can safely reach it, after the ratio of petrol to what that tank holds.
Three queries come first, before any quote, rather than after — what was put in, how much, has it run — and this is the reason. Those replies turn a range into a straight figure.
About Whitehill, for a moment
Whitehill is a suburban area in Staffordshire, situated approximately 5 miles from Stoke-on-Trent, and is characterised by its semi-detached housing stock. Whitehill sits at an elevation of around 187 metres, in the inland landscape of the West Midlands region. Whitehill is close to nearby places such as Dove Bank, Kidsgrove, and Newchapel, and is home to a population of around 4706 residents. Whitehill is located about 140 miles northwest of London, making it a relatively accessible location.
Whitehill and Staffordshire: where our fuel drain cover reaches
Petrol in diesel jobs around Whitehill — part of the ST postcode area — go to teams that also cover the locations about it, Dove Bank, Kidsgrove and Newchapel included. A forecourt, a supermarket car park, a lay-by or your own driveway are all locations our technicians drain, and your car does not need to move to us.
Still at the petrol pump around Whitehill?
Then you're in the best spot there is. Keep the vehicle turned off, then ring.