Should You Worry? Petrol in a Diesel Car in Westcotes
Likely less than you are now — provided nobody has started the car. Until the ignition primes the pump, the starter turns, or your vehicle is driven, petrol in a diesel tank simply sits there and does nothing. Which makes the truthful reply to the first Westcotes question — "have I ruined it?" — usually no. Keep it that way: leave your engine off then call Petrol in Diesel. Keep reading for three things: the effect petrol has inside a diesel engine, the signs of how far it has spread, and ways to make sure you never do it again.
The motor and petrol in a diesel: what goes on
On its way through a motor, diesel does two jobs. Oiling comes before burning; it does both. Extremely fine gaps go into the injectors and the high-pressure fuel pump, and just your diesel running through stops those surfaces grinding together.
Petrol does the first job poorly and the second not at all. The knocking comes from petrol being designed not to ignite when compressed, which is precisely the opposite of what a diesel needs. On top of that it is thinner than diesel, it strips away the protection the system hinges on, and any pump running on that blend is wearing itself.
Combined, those make the shape of the problem clear. The harm is done by circulation, not by contact. Where that petrol is only inside the tank, it's a fault of fuel, nothing more. Whatever a worn pump sheds goes on, borne by your fuel, into the fuel injectors downstream, which is why a pump that has been working on that petrol is where a mechanical problem starts.
Westcotes, petrol in a diesel: four cases, from mild to serious
The best case there is: filled up, never started. That petrol is in the tank and just that tank, and the job is a drain and a flush where the vehicle sits. This is the one scenario that can only truly happen at a forecourt, because anywhere else your car has been driven to get there.
Ignition on, or started for a moment. Petrol has left your tank and got to the fuel filter and the lines, because your system has been bled. Drain, flush, deal with the fuel filter: still usually easy.
Those few miles on the road were your pump running on fuel diluted by petrol the whole way. Tank, lines, filter, then clean fuel put through the whole circuit: that's the work, and the way the vehicle was driven counts as much as the distance. On the school run to Shaftesbury Junior School, the distance is short. Very different a second time: a trip to Leicester, under 3 miles away, or some distance on the M1, under 3 miles from Westcotes, where the motor kept working hard.
Driven on till it protested — knocking, smoke, an uneven idle, a soft throttle. What you are hearing is the engine signalling fuel that no longer behaves like diesel. Pull up wherever you are — the verge on Barclay Street, a lay-by, a side street — and leave the car where it is. What goes first is still the drain and flush-through, and that sorts it out, with permanent damage very uncommon when a vehicle is stopped quickly.
Petrol in a diesel myths Westcotes motorists hear
"Top it up the rest of the way with diesel and it will be fine" — a myth. It will not. Nothing is removed by topping up — you are left with a bigger tank, still the same mixture. The assumption behind that advice — that diesel fuel systems tolerate petrol by percentage — is wrong.
Not so: a newer diesel copes with a bit of petrol. Rather, the reverse. Protection counts more on modern diesels, not less, because their fuel runs through more precise components at higher pressure.
"It starts, it drives, so no harm done" — the myth that trips up most motorists than any other. A petrol engine fed diesel generally won't run, and so the motorist stops and the damage stops with them. Feed petrol to a diesel and it normally fires up, idles and pulls away as if nothing happened — all while its pump is wearing. A running engine does not mean fine.
"A drop of two-stroke oil and drive it home" — a myth, borrowed from a fix from years ago, for a distinct fault. It doesn't put back what petrol has thinned, and the petrol is still inside that tank later on.
"Drain it yourself and you're sorted" — a myth, since after it's been running some petrol sits in the filter and lines, waiting to go straight back through your pump on the next start. It's also genuinely hazardous to drain petrol into a can by the kerbside.
How it happens: petrol in a diesel
On purpose? Never. Through carelessness? Rarely, if ever. The forecourt makes it simple: the petrol nozzle is the smaller of the two, and it slips into a diesel filler with almost no resistance, while a diesel nozzle generally won't go into a petrol vehicle at all. So the mistake runs one way.
The moment routine stops matching the car is the moment it takes place. Courtesy car, hire car, or a vehicle that's new. Two cars on one driveway, one petrol, one diesel. Your usual forecourt, its pumps suddenly in a different order. Racing for a train at Leicester and filling up en route. A new-to-you diesel Renault Megane, its first fuelling, and a driver used to petrol: precisely when it takes place. Throw in a back seat full of kids, a phone call or rain, and the hand takes over.
How to prevent petrol in a diesel at your next fill-up around Westcotes
- Green for unleaded and black for diesel is normal in the UK — but not on each forecourt. Go by the label on the pump, not the colour.
- Many cars state the fuel type inside the filler flap or on the cap, and so check there on your first fill in any vehicle you don't know.
- One of each in the house? Mark the key to the diesel — a bright fob, a sticker — because intending to remember is not enough.
- Before the nozzle comes off the petrol pump the first time you fill a hired or new motor, say "diesel" out loud. Silly, yes, but it does the trick.
- While you are thinking about something else, this is an easy mistake to make — so put the phone away.
- A misfuel inhibitor helps, up to a point. Some diesels have a filler built to refuse a petrol nozzle, and add-on devices exist for cars without one. They are a safety net, not a reason to stop reading the pump.
- Less petrol makes a weaker mixture, and so stop the moment you realise — while remembering that your next stage is unchanged. It is still not to start the car.
Already put petrol in a diesel around Westcotes?
In that case, there's just a short order of things. Don't fire it up, and don't switch your ignition on. If you are still at the forecourt — Shell or anywhere else — ask the attendants to help you push it away from the petrol pump. Next, 0333 366 0103. We'll ask what went in, roughly how much, and if it has been run.
If it was AdBlue and not petrol, say so. That is a different fault — corrosion and deposits instead of lost lubrication — and it has its own page for Westcotes.
One petrol in a diesel job around Westcotes costs more than another. Why?
The four scenarios above are four different tasks, so no single quote for this would be honest. The situation itself does most of the work of moving your cost. After that it is the ratio — how much petrol went in against how much the tank takes — and then where your car is and whether a van can get to it safely.
Ahead of any quote, not after, come three questions: the fuel that went in, its volume, and if it has run. That is why. Those answers change a range into a straight figure.
About Westcotes and its setting
Westcotes is a suburban area located on the outskirts of Leicester, situated near the River Soar in Leicestershire. Westcotes sits at an elevation of 66 metres, with its riverside setting influencing the local environment. Westcotes is characterized by its predominantly terraced housing stock, reflecting the area's historical development as a residential suburb of Leicester.
Fuel drain cover in Westcotes and across Leicestershire
Westcotes rests in the LE postcode area, and the vans that answer petrol in diesel jobs there work the spots around it as well — New Found Pool, Black Friars and Leicester among them. A forecourt, a supermarket car park, a lay-by or your own drive are all locations our engineers work, and your car does not need to move to us.
Still at the pump in Westcotes?
Then you are in the best place there is. Keep it turned off, then ring.