How Worried Should You Be? Petrol in a Diesel Car in Sidemoor
Provided it hasn't been started, worry far less than you likely are. Till the ignition primes your pump, your starter cranks, or the car is driven, petrol in a diesel tank just sits there and does nothing. Which means the honest reply to the first Sidemoor query — "have I ruined it?" — usually no. To keep the vehicle that way, ring Petrol in Diesel then leave the motor alone. Keep reading 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 do it again.
Petrol in a diesel: what does it do to the engine?
Two jobs fall to diesel on its journey through a motor. It protects to begin with, and after that does it burn. Built to extremely fine clearances, the fuel injectors and the pump depend on the diesel moving through them to stop their surfaces wearing against one another.
Of those two tasks, petrol manages the first poorly and the second never. It is runnier than diesel and takes away the lubrication your fuel system rests on, so a pump running on a petrol mixture is a pump wearing itself. And petrol is designed to resist igniting under compression, which is the reverse of what a diesel needs from its fuel. That's where the knocking comes from.
The shape of the trouble is plain when you put those together. It's circulation that causes the damage, not contact. Any tank with petrol in it is a fuel fault. The beginning of a mechanical problem is a pump that has been working on that petrol — and whatever a worn pump sheds travels on with the fuel to your injectors beyond it.
How bad is petrol in a diesel? Four scenarios we see around Sidemoor
Filled up, and not started: no case is better. The petrol is inside that tank and just the tank, and the task is a drain and a flush where your car stands. This is the one scenario that can only truly occur at a forecourt, because anywhere else the vehicle has been driven to get there.
Started for a moment, or only the ignition on. Petrol has come out of your tank and reached your filter and your lines, because the system has been bled. That is generally still a straightforward task — a drain, a flush, and your filter seen to.
A few miles driven, and your pump has spent every one of them running on thinned fuel. Tank, lines, filter, then fresh fuel put through the entire system: that's this work, and the way your car was driven counts as much as the mileage. The school run to Meadows First School is one matter. Any mileage on the M5, under a mile from Sidemoor, means the engine working hard throughout, and a run to Birmingham, under 15 miles away, makes a very different job as well.
Driven on until it complained — clattering, smoke, a ragged idle, a dead throttle. The motor is telling you the fuel is no longer acting like diesel. Pull up where you are — on the verge on Broad Street, at the kerb, down a side road — and don't move it again. A car pulled over early very rarely has long-term damage, because the drain and the flush, which still come first, take care of it.
Petrol in a diesel stories Sidemoor motorists hear
"Top it up the rest of the way with diesel and it'll be fine" — a myth. It won't. Nothing is removed when you top up — your tank simply carries more of the same mixture. That guidance assumes a diesel fuel system tolerates petrol by percentage. It doesn't.
If anything, the reverse is true. Myth: "A newer diesel can cope with a bit of petrol." At higher pressure, through finer components: that is how a current diesel moves its fuel, and so the lubrication matters more, not less.
One myth that catches drivers off guard: if it starts and drives, it must be unharmed. Feed diesel to a petrol engine and it normally won't run, so the motorist stops — and the harm stops with them. A diesel fed petrol usually starts, idles and drives away as though nothing has happened, while the pump wears. A running engine does not mean fine.
An old workaround for a different fault is behind this one. Myth: "Add some two-stroke oil and drive it home." It doesn't put back what petrol has weakened, and the petrol is still inside the tank later.
If the motor has been run, part of that petrol is in the fuel filter and your lines, not your tank — and the next start pulls it straight back through the pump. So the myth "drain the tank yourself and you're sorted" doesn't stand up. On top of that, petrol drained into a can by the road is truly hazardous.
Petrol in a diesel: how does it take place?
It's seldom carelessness, and nobody does it on purpose. The forecourt makes it easy: the petrol nozzle is the narrower of the two, and it slips 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.
It occurs when habit and the car stop matching. Any car that is new to you — a hire car, on loan as a courtesy car, or just bought. A household with one petrol and one diesel on the driveway. Your normal forecourt, its pumps suddenly in a different order. A train to catch, and a hurried fill on the way to Bromsgrove. The first fill-up in a diesel Volkswagen Golf after years of driving petrol is precisely the moment it takes place. With rain, a call arriving, or children to deal with, your hand simply does what it has always done.
How to avoid petrol in a diesel on your next fill-up around Sidemoor
- Green for unleaded and black for diesel is usual in the UK — but not on each forecourt. Trust the label on the pump, not the colour.
- In a car you don't know, look inside the flap over the filler or at the cap before your first fill: plenty of motors print the fuel type there.
- Good intentions count for less than a sticker or a fob in a bright colour on your diesel's key if a home has one of each. So label it.
- It sounds daft and it does the trick: on the first fill in a new or hired car, say "diesel" out loud before you lift the nozzle off the petrol pump.
- Put the phone away. This is an easy mistake to make whilst you're thinking about something else.
- A misfuel inhibitor helps, up to a point. Some diesels have a filler built to block a petrol nozzle, and add-on devices exist for motors without one. They are a safety net, not a reason to stop checking the pump.
- Noticing it halfway? Stop at once. A weaker mixture results from less petrol inside your tank, yet your next stage remains the same: don't crank it.
Petrol already in a diesel in Sidemoor? Begin here
Then, there is just a short order of things. Don't switch the ignition on, and do not fire it up. The attendants on the forecourt — whether at BP itself or wherever you filled up — will normally help roll it away from the petrol pump if you ask. Next, 0333 366 0103. We will ask what got in, roughly how much, and if it has been run.
AdBlue, not petrol? Then tell us. Corrosion and deposits, not lost protection, make it a different fault — Sidemoor has a page just for it.
One petrol in a diesel task around Sidemoor costs more than another. Why?
The four situations above are four separate jobs, so no single price for this would be fair. The scenario itself does most of the work of moving your cost. Where the vehicle is counts too, and whether our van can safely reach it, after the proportion of petrol to what the tank holds.
Three queries come first, before any quote, rather than after — what got in, how much, has it run — and this is the reason. Their answers are what change a range into one firm number.
About Sidemoor itself
Sidemoor is a suburban area in Worcestershire, situated on the riverside at an elevation of around 92 metres. Sidemoor lies approximately 11 miles south of Birmingham and 100 miles northwest of London, with nearby places including Perryfields and Bromsgrove. Sidemoor has a population of around 6485 people, predominantly living in semi-detached housing. Sidemoor is part of the wider West Midlands region, with the nearby town of Red Cross also being a local point of interest.
Fuel drain cover across Worcestershire, Sidemoor included
Perryfields, Bromsgrove and Red Cross are among the locations near Sidemoor that the same teams work, answering petrol in diesel jobs across Sidemoor's B postcode area. No need to bring your vehicle to us. Forecourts, supermarket car parks, lay-bys and your own drive are all places we drain.
Sidemoor: still at the pump?
No position is better: that's where you now are. Call, and keep it switched off.