How Worried Should You Be? Petrol in a Diesel Car in Killerby
If it hasn't been started, worry less than you likely are. Petrol resting in a diesel tank does nothing to your motor till something draws it through the fuel system — the ignition priming the pump, the starter, or driving on its own. So the fair answer to the first question everyone in Killerby asks, "have I ruined it?", is usually no. Keep it like that: leave the motor off then call Petrol in Diesel. What petrol actually does to a diesel, how to gauge how far it has travelled, and how to stop it from happening a second time: that is the rest of this page.
Inside your engine: what petrol in a diesel does
Passing through an engine, diesel is doing two things at the same time. Lubricating comes before burning; it does both. What stops the surfaces inside the high-pressure pump and the fuel injectors from wearing down against each other is your diesel flowing through them — they are built to very fine clearances.
Poorly at the first, not at all at the second: that is petrol. A pump working on a petrol blend is wearing itself out, because petrol is thinner than diesel and strips out the protection the fuel system depends on. Petrol is also designed to resist igniting under compression — the opposite of what a diesel wants from its fuel — and that is where any clattering comes.
The shape of the issue is clear once you put those together. It's movement that causes the damage, not contact. All a tank with petrol in it amounts to is a fuel issue. A pump that has been working on that petrol is the beginning of a mechanical one, and whatever a worn pump sheds moves on with your fuel to the fuel injectors further on.
Killerby, petrol in a diesel: four cases, from mild to major
The best case there is: filled up, never started. The petrol is in the tank and only that tank, and the task is a drain and a flush where the car sits. This is the one scenario that can only truly happen at a forecourt, as anywhere else your car has been driven to get there.
Started for a second, or only the ignition on. With your system primed, the fuel lines and filter now contain petrol that came from the tank. Drain, flush, see to your filter: still usually simple.
The pump now spent a few miles on thinned fuel — that is what driving the car does. Miles is only half of that; how hard it was driven matters equally. Either way the work runs to that tank, your lines, the fuel filter and clean fuel through the entire circuit. The school run to Cayton Community Primary School is one matter. Driving as far as Kingston upon Hull, under 50 miles away, makes a very different task — as does any distance on the Petuaria Way, under 50 miles from Killerby, with your engine labouring hard all the way.
Driven till it protested. Clattering, an uneven idle, smoke, a throttle that has gone soft. What you are hearing is your engine signalling fuel that no longer acts like diesel. Pull up where you are — on the verge on Main Street, at the kerb, down a side road — and do not move it again. The fuel drain and flush still come first, and they take care of it: if a car is pulled over early, long-term damage is very unusual.
Killerby people and that petrol in a diesel stories they hear
It will not be fine. The myth: "Fill it the rest of the way with diesel and it will be." A bigger tank of the same mix is all you get, since topping up removes nothing. Percentage isn't how a diesel fuel system tolerates petrol, however much that guidance supposes.
"Modern diesels can handle a little petrol" — a myth, and closer to the opposite. Smaller parts and higher pressure are how a current diesel runs its fuel, and that makes the protection count more, not less.
This is the one that catches motorists. Myth: "If it starts and drives, there is no harm done." Any petrol engine fed diesel generally won't run, and so the driver stops and the damage stops with them. Nothing looks to have happened when a diesel fed petrol fires up, ticks over and drives away, which it usually will; meanwhile the pump wears. Running is not the same as fine.
An outdated fix for a different issue lies behind this one. Myth: "Add some two-stroke oil and drive the vehicle home." It doesn't put back what petrol has weakened, and that petrol is still in the tank after that.
"Drain it yourself and you are sorted" — a myth, since after it's been running some petrol sits in the fuel filter and lines, ready to go straight back through your pump at the next start. It is also truly risky to drain petrol into a can at the roadside.
Petrol in a diesel: how does it occur?
On purpose? Never. Through carelessness? Rarely, if ever. The petrol nozzle is the slimmer of the two and slides into a diesel filler with almost no resistance; a diesel nozzle mostly will not go into a petrol car at all. The forecourt makes it easy, and the slip runs one way.
Routine and the car falling out of step is how it happens. Courtesy car, hire car, or a car that's new. Two motors on one drive, one petrol, one diesel. A forecourt you know, only with its pumps laid out differently. Filling up in a rush en route to Seamer, with a train to catch. The first fill-up in a diesel Volkswagen Golf after years of driving petrol is exactly the moment it occurs. With rain, a call arriving, or a car full of children to deal with, your hand just does what it has always done.
Next time you fill up in Killerby: preventing petrol in a diesel
- Read the petrol pump, not the colour. In the UK unleaded handles are usually green and diesel black, yet not on each forecourt. The label is what matters.
- Plenty of motors state the fuel inside your filler flap or on the cap, so check it on your first fill in a motor you don't know.
- One of each in the house? Mark your key to your diesel — a coloured fob, a sticker — since meaning to remember is not enough.
- Before the nozzle comes off the pump the first time you fuel a hired or new motor, say "diesel" aloud. Daft, perhaps, but it does the trick.
- Mistakes like this are easy to make whilst your mind is on something else, so your phone goes away.
- A misfuel inhibitor helps, up to a point. Some diesels have a filler designed to block a petrol nozzle, and add-on devices exist for vehicles without one. They are a backstop, not a reason to stop reading the petrol pump.
- Stop as soon as you notice. Less petrol inside that tank makes a thinner mixture. It doesn't change what to do next, which is still not to fire it up.
Already put petrol in a diesel in Killerby?
Short and simple, then, is the order of things. Leave it unstarted, with the ignition switched off too. Still at the forecourt, at JET or anywhere else? Ask the attendants to help you roll the vehicle clear of the petrol pump. Phone 0333 366 0103 next, with three facts — your fuel, the approximate amount, and if it has run.
If it was AdBlue rather than petrol, say so. That's a different problem — corrosion and deposits rather than lost protection — and it has its own page for Killerby.
What makes one Killerby petrol in a diesel job cost more than the next
Four separate jobs lie behind the four situations above — which is why there is no honest single quote. The scenario itself does most of the work of moving your cost. The proportion matters next, meaning how much of your tank is petrol, and then the position of the vehicle and whether reaching it is safe for our van.
What was put in, how much, and whether it's run — three queries our engineers ask before costing, not after, for precisely that reason. Given those replies, you get a straight figure instead of a range.
About Killerby
Killerby is a small coastal hamlet in North Yorkshire, situated near the villages of Lebberston and Cayton. Killerby lies at an elevation of 38 metres, within a short distance of the coast and approximately 33 miles from Kingston upon Hull. Killerby has a population of around 546 people, predominantly living in semi-detached housing. Killerby is located near Osgodby, in a scenic area of Yorkshire's coastline.
Killerby and North Yorkshire: where our fuel drain cover reaches
Lebberston, Cayton and Osgodby are among the spots around Killerby that the same vans work, answering petrol in diesel jobs across Killerby's YO postcode area. Our technicians drain where the car is — your own drive, a lay-by, a supermarket car park, a forecourt — so it does not have to come to us.
At the petrol pump in Killerby, right now?
The best place there is, then — that's where you are. Phone, and keep it switched off.