Lynnwood: Petrol in a Diesel Car? How Worried to Be
If it has not been started, you can worry far less than you likely are. "Have I ruined it?" is the first thing everyone around Lynnwood asks, and the truthful answer is usually no, since petrol left in a diesel tank hurts nothing until it is drawn through the system — by ignition priming, by your starter, or by driving. Leave your motor off and call Petrol in Diesel — that is how you keep it like that. The rest of this page sets out what petrol actually does to a diesel, how to tell how far it has got, and how to make sure it doesn't happen to you again.
What petrol in a diesel does to the motor
Passing through a motor, diesel does two jobs at the same time. It lubricates first, and after that does it burn. Extremely fine gaps are built into your injectors and the high-pressure fuel pump, and only the diesel flowing through keeps their surfaces from grinding together.
Badly at the first, not at all at the second: that's petrol. 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 system rests on, and any pump running on that mix is wearing itself.
Seen together, they show the shape the trouble takes. Contact does not do the damage — movement does. Petrol in the tank is a fuel issue. Whatever a worn pump sheds travels on, borne by your fuel, into your injectors downstream, which is why a pump that has been working on that petrol is where a mechanical fault begins.
Four scenarios we see in Lynnwood: how serious is petrol in a diesel?
Fuelled up, never started. The best case there can be. Just the tank has petrol in it, and so the job is emptying that tank and rinsing the system where the car stands. This scenario can only truly happen on a forecourt: anywhere else, your car got there by being driven.
Started for a second, or only the ignition on. The system has been bled, so petrol has left that tank and reached the filter and the fuel lines. That's usually still an easy task — a drain, a flush, and your filter dealt with.
A couple of miles driven, and the pump has spent each of them labouring on diluted fuel. Mileage is only half of that; how hard it was driven matters equally. Either way the work includes the tank, your lines, the fuel filter and fresh fuel through the whole system. On the school run to the local primary school, the distance is short. Very different once more: a run to Carlisle, under 50 miles away, or any distance on the A74(M), under 50 miles from Lynnwood, where the engine never stopped working hard.
Driven until it complained. Rattling, a ragged idle, smoke, a throttle that has gone soft. That's your engine telling you its fuel no longer is behaving like diesel. Pull up where you are — on the verge on Haggis Ha' Brae, at the kerb, down a side road — and don't move it again. A car stopped early very seldom has permanent damage, since the drain and the flush, which still go first, deal with it.
What Lynnwood drivers get told about petrol in a diesel — and the myths in it
"Top it up the rest of the way with diesel and it'll be fine" — a myth. It will not. A fuller tank of the same mixture is all it gives, since topping up removes nothing. That advice supposes a diesel fuel system handles petrol by percentage. It doesn't.
Myth: "A current diesel can cope with a bit of petrol." If anything, the opposite. Lubrication counts more on current diesels, not less, since their fuel runs through more precise parts at higher pressure.
"It starts, it drives, and so no harm done" — the myth that catches most drivers than any other. Feed diesel to a petrol engine and it normally won't run, so the driver stops — and the harm stops with them. A diesel fed petrol normally starts, idles and drives away as if nothing has happened, while the pump grinds. Running isn't the same as fine.
Myth: "Add some two-stroke oil and drive the car home." It's an old workaround for a separate fault. It does not put back what petrol has diluted, and the petrol is still inside your tank afterwards.
"Drain it yourself and you're sorted" — a myth, because after it has been running some petrol lies in your filter and lines, waiting to go right back through the pump at your next start. Also, a can of petrol drained by the roadside is truly dangerous.
How it happens: petrol in a diesel
It is seldom carelessness, and no one does it on purpose. The petrol nozzle is the narrower of the two and slides into a diesel filler with almost no resistance; a diesel nozzle mostly will not go into a petrol vehicle at all. The forecourt makes it simple, and the error runs one way.
It happens when routine and the car stop matching. Hire cars, courtesy cars, and vehicles that are new to you. Households running one of each, petrol and diesel. A forecourt you know, but with its pumps laid out differently. Rushing for a train outside the nearest station and fuelling up en route. Exactly the moment it happens: after years of driving petrol, a driver fills a diesel BMW 3 Series for the first time. The hand repeats what it has always done once you add rain, a phone call or a back seat full of children.
Lynnwood drivers: how to prevent petrol in a diesel next time
- The label is what counts, and so check the pump rather than the colour: in the UK unleaded handles are usually green and diesel black, but not on each forecourt.
- Check your filler flap. Plenty of motors state the fuel inside the flap or on the cap. Look at it on the first fill in any vehicle you do not know.
- One of each in the household? Mark your key to your diesel — a coloured fob, a sticker — because meaning to remember is not enough.
- "Diesel", aloud, before you pick up the nozzle — every time a new or hired car needs its first tank. It sounds silly. It does the trick.
- Whilst you're thinking about something else, this is an easy mistake to make — so tuck your phone away.
- A misfuel inhibitor helps, up to a point. Some diesels have a filler designed to refuse a petrol nozzle, and add-on devices are available for motors without one. They are a safety net, not a reason to stop reading the pump.
- Spotting it mid-fill? Stop at once. A thinner mix follows from less petrol in your tank, but the next step stays the same: don't fire it up.
Petrol already in a diesel in Lynnwood? Start here
In that case, there's only a short order of things. Leave it unstarted, with the ignition off too. Ask the staff to help you push it clear of the pump if you're still on the forecourt, whether that's Sainsbury's or somewhere else. Then call 0333 366 0103 and tell us what was put in, roughly how much, and if it has run.
Say so if it was AdBlue instead of petrol: it is a different fault, with its own page for Lynnwood, because AdBlue brings corrosion and deposits rather than lost protection.
Why one petrol in a diesel job around Lynnwood costs more than another
There is no fair single quote for this, because the four situations above are four separate tasks. Chiefly, your cost moves with which one you're in. Where the vehicle is counts too, and whether a van can safely reach it, after the ratio of petrol to what the tank holds.
Three queries come first, before quoting, rather than after — what was put in, how much, has it run — and that is the reason. The replies turn a range into a straight figure.
About Lynnwood itself
Lynnwood is a riverside locality in the Scottish Borders, situated near the towns of West End and Cauld, with Wilton Dean also nearby. Lynnwood sits at an elevation of 156 metres, close to the River Teviot, and is characterized by predominantly flat housing. Lynnwood is located approximately 36 miles from Carlisle and 291 miles from London, making it a relatively remote community. Lynnwood has a population of around 896 residents.
Across Scottish Borders and in Lynnwood: fuel drain cover
Petrol in diesel call-outs in Lynnwood — part of the TD postcode area — go to vans that also cover the spots around it, West End, Cauld and Wilton Dean included. The vehicle doesn't need to move to us: we drain at a forecourt, in a supermarket car park, in a lay-by or on your own driveway.
Still at the pump in Lynnwood?
Then you are in the best position there can be. Call, and leave it turned off.