Petrol in a Diesel Car in Lostock Hall: How Worried Should You Be?
Not started? Then less worried than you probably are. Everyone around Lostock Hall starts with "have I wrecked it?", and the fair answer is usually no: petrol left in the tank of a diesel remains harmless till priming, cranking or driving pulls it into your fuel system. Petrol in Diesel is who to call, with the motor kept off, and so it stays that way. Read on for three things: the effect petrol has inside a diesel engine, the clues of how far it has got, and ways to make sure you never repeat it.
Petrol in a diesel: what does it do to the motor?
Two jobs fall to diesel on its journey through a motor. Before it burns, it lubricates — and then it burns. What keeps the surfaces inside your high-pressure pump and the injectors from grinding against one another is your diesel passing through them — they're designed to very fine clearances.
Petrol does the first task poorly and the second not at all. Being less viscous than diesel, petrol strips out the protection a fuel system needs, so a pump on that mixture to wear itself. It is equally made to resist igniting under compression — the opposite of what a diesel needs — which is where you get the knocking.
The shape of the trouble is clear when you put those together. The harm is done by movement, not by contact. All a tank with petrol in it amounts to is a fuel issue. A pump that has been running on that petrol is the beginning of a mechanical one, and whatever a worn pump sheds travels on with the fuel to the injectors downstream.
Four scenarios we see in Lostock Hall: how bad is petrol in a diesel?
Fuelled, and not started: nothing beats it. Only that tank has petrol in it, so the task is emptying your tank and purging the fuel system where the car stands. This situation can only truly occur at a forecourt: anywhere else, your car got there by being driven.
Started for a moment, or only the ignition on. Petrol has come out of that tank and got to the filter and the fuel lines, since your system has been bled. That is usually still a simple task — a drain, a flush, and your filter seen to.
Those few miles driven were your pump labouring on fuel diluted by petrol throughout. The work is your tank, your lines, your filter and clean fuel through the whole circuit, and how hard your car was driven matters as much as how far. Short trips, like the school run to Our Lady and St Gerard's Roman Catholic Primary School, Lostock Hall, are one matter. Driving as far as Preston, under 3 miles away, makes a very different job — as does any miles on the M65, under a mile from Lostock Hall, with your engine working hard the whole time.
It complained, and only then stopped: smoke, clattering, a throttle gone soft, an idle gone ragged. The fuel isn't acting like diesel any more, and your motor is telling you. Leave it where it has stopped: a lay-by, a side street, the verge on Victoria Street. Lasting damage is very uncommon if a vehicle is pulled over quickly, and the drain and flush-through that still come first sort it out.
What Lostock Hall drivers get told about petrol in a diesel — and the myths in it
Myth: topping up to full with diesel makes it fine. It doesn't. Nothing comes out when you top up — the tank simply holds more of the same mixture. The idea behind the guidance — that diesel fuel systems tolerate petrol by percentage — is wrong.
"Newer diesels can handle a little petrol" — a myth, and closer to the reverse. A newer diesel runs its fuel through more precise components at higher pressure, which makes the lubrication count more, not less.
This is the one that catches people. Myth: "If it starts and drives, there's no harm done." Diesel in a petrol motor normally means a motor that won't run: the driver stops, and so does the damage. A diesel fed petrol generally starts, ticks over and drives away as if nothing has happened, whilst the pump wears. Fine and running are not the same thing.
"A drop of two-stroke oil and drive it home" — a myth, borrowed from a fix from years ago, for a separate issue. It doesn't put back what petrol has weakened, and the petrol is still in the tank later.
The next start sends petrol back round the pump from your lines and the fuel filter, where some of that ends up after the engine has been run. That's why a DIY tank drain doesn't sort it — a myth. Also, a can of petrol drained by the kerbside is truly dangerous.
How does petrol in a diesel happen?
Carelessness is seldom the cause, and no one means to do it. The forecourt makes it easy: the petrol nozzle is the smaller of the two, and it slides into a diesel filler with almost no resistance, while a diesel nozzle generally won't go into a petrol vehicle at all. So the error runs one way.
It takes place when habit and the car stop matching. Courtesy car, hire car, or a car that's brand new. Households running one of each, petrol and diesel. A familiar forecourt with the pumps in a different order. Fuelling up in a rush en route to the nearest station, with a train to catch. Exactly the moment it takes place: 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 the hand does what it has always done.
How to prevent petrol in a diesel on your next fill-up in Lostock Hall
- Read the petrol pump, not the colour. In the UK unleaded handles are generally green and diesel black, yet not on every forecourt. The label is what matters.
- Check your filler flap. Many vehicles state the fuel type inside the flap or on the cap. Look at it on your first fill in any vehicle you don't know.
- Good intentions count for less than a sticker or a fob in a bright colour on the diesel's key if a home has one of each. So label it.
- "Diesel", out loud, before you pick up the nozzle — each 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 put your phone away.
- Add-on devices exist for vehicles without one, and some diesels come with a filler that won't take a petrol nozzle. Helpful — but a backstop at best, never a reason to stop checking the label.
- Spotting it halfway? Stop there and then. A thinner blend follows from less petrol inside the tank, but the next stage stays the same: don't fire it up.
Petrol already in a diesel around Lostock Hall? Start here
Then the order of things is short. Do not switch the ignition on, and do not start it. Ask the staff to help you roll it away from the pump if you're still on the forecourt, whether that's Shell or anywhere else. Next, 0333 366 0103. We will ask what went in, roughly how much, and if it has been run.
AdBlue, not petrol? Then say so. Corrosion and deposits, not lost protection, make it a different fault — Lostock Hall has a page just for it.
Lostock Hall petrol in a diesel jobs: why one costs more than another
There is no fair single quote for this, since the four scenarios above are four separate tasks. The scenario itself does most of the work of moving your cost. Two things follow that: the petrol that was put in as a share of what the tank takes, then the spot the car is in and whether our van can reach it safely.
Ahead of any quote, not after, we ask three questions: the fuel that got in, its quantity, and if it's run. That's why. Their replies are what turn a range into one firm number.
About Lostock Hall itself
Lostock Hall is a locality situated on the banks of the River Lostock in Lancashire, with a mix of semi-detached housing and local amenities. Lostock Hall lies close to the city of Preston, approximately 2.6 miles away, and is part of the wider North West region. Lostock Hall has a population of around 3849 people and is near other local places such as Tardy Gate and Farington Moss. Lostock Hall's riverside setting and relatively low elevation of 41 metres contribute to its geographical character.
Fuel drain cover across Lancashire, Lostock Hall included
Petrol in diesel call-outs around Lostock Hall — part of the PR postcode area — go to teams that also cover the locations round it, Tardy Gate, Farington Moss and Cuerden Green included. A forecourt, a supermarket car park, a lay-by or your own drive are all places we drain, and your car does not need to come to us.
At the pump in Lostock Hall, right now?
Then you are in the best spot there can be. Keep the car switched off, then ring.