How Worried Should You Be? Petrol in a Diesel Car in Butterrow
Unstarted? Then less worried than you likely are. Everyone in Butterrow starts with "have I wrecked it?", and the fair answer is generally no: petrol left inside your tank of any diesel remains harmless till priming, cranking or driving draws it into the fuel system. To leave it that way, ring Petrol in Diesel and leave the motor alone. What petrol actually does to a diesel, how to judge how far it has travelled, and how to keep it from happening again: that's the remainder of this page.
The engine and petrol in a diesel: what goes on
Diesel does two jobs on its way through an engine. Lubricating comes before burning; it does both. The high-pressure fuel pump and your injectors are made to extremely fine gaps, and your diesel passing through them is what keeps those surfaces from wearing against one another.
The second job petrol does not do at all, and the first it does poorly. A pump running on a petrol blend is wearing itself out, since petrol is thinner than diesel and strips out the protection your fuel system relies on. Petrol is also made to resist igniting under compression — the reverse of what a diesel needs from its fuel — and that's where the rattling comes.
Put those together and the shape of the trouble is plain. The damage is done by circulation, not by contact. Any tank with petrol in it is a fuel fault. The start of a mechanical one is a pump that has been running on that petrol — and whatever a worn pump sheds moves on with the fuel to your injectors downstream.
Petrol in a diesel in Butterrow: how bad is it? Four situations
Filled up, never started. The best case there can be. The petrol is in your tank and only the tank, and the task is a drain and a flush where your car stands. This is the one situation that can only really take place on a forecourt, because anywhere else the car has been driven to get there.
Ignition on, or started for a second. Once primed, the system has pulled petrol from the tank as far as the filter and the lines. Normally little more than draining, flushing and seeing to the filter, so still simple.
Your pump now spent a few miles on weakened fuel — that is what driving it meant. Tank, lines, filter, then fresh fuel run through the entire system: that's this work, and the way the car was driven matters as much as the distance. Short trips, like the school run to Stroud Valley Community Primary School, are one matter. Driving as far as Gloucester, under 10 miles away, makes a very different task — as does any miles on the M5, under 5 miles from Butterrow, with the motor running hard all the way.
Driven on till it protested — rattling, smoke, a ragged idle, a soft throttle. The fuel isn't acting like diesel any more, and the engine is saying so. Whether it is the verge on Butterrow Lane, a lay-by or a side road, stop there and leave it. The drain and flush still go first, and they take care of it: when a vehicle is pulled over quickly, long-term damage is very unusual.
Butterrow motorists and the 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." Topping up removes nothing; it gives you a fuller tank of the same mix. A diesel fuel system does not tolerate petrol by percentage in the way that advice presumes.
"Newer diesels can handle a little petrol" — a myth, and nearer the opposite. At higher pressure, through more precise components: that is how a newer diesel moves its fuel, so the lubrication counts more, not less.
This is the one that fools drivers. Myth: "If it starts and drives, there is no damage done." Diesel in a petrol motor usually leaves a motor that won't run: the motorist stops, and so does the harm. Feed petrol to a diesel and it normally starts, idles and drives away as if nothing happened — all while its pump is wearing. Running does not mean fine.
An old workaround for a separate problem lies behind this one. Myth: "Add some two-stroke oil and drive the vehicle home." The petrol is still in your tank after that, and what it has weakened is not put back.
Myth: "Drain that tank yourself and you are sorted." After the engine has been run, some of that petrol is no longer inside that tank: it is in your filter and the fuel lines, and it goes straight back through the pump at your next start. Besides, petrol emptied into a can by the road is truly risky.
Petrol in a diesel: how does it happen?
A careless moment is seldom the cause, and no one means to do it. The petrol nozzle is the narrower of the two and slides into a diesel filler with almost no resistance; a diesel nozzle mostly won't go into a petrol motor at all. The forecourt makes it easy, and the slip runs one way.
When routine and the vehicle stop matching, it takes place. Hire cars, courtesy cars, and vehicles that are new to you. A household with one petrol and one diesel on the drive. Your ordinary forecourt, its pumps now in a different order. Fuelling up in a hurry en route to Stroud, with a train to catch. A new-to-you diesel BMW 3 Series, its first fuelling, and a driver accustomed to petrol: precisely when it occurs. With rain, a call arriving, or a car full of children to deal with, the hand simply does what it has always done.
How to prevent petrol in a diesel on your next fill-up in Butterrow
- Green for unleaded and black for diesel is normal in the UK — but not on each forecourt. Trust the label on the pump, not the colour.
- In a motor you don't know, look inside the flap over the filler or at the cap before the first fill: plenty of vehicles print the fuel type there.
- A coloured fob or a sticker on your diesel's key achieves more than any amount of meaning to remember, in a household with one of each.
- Before the nozzle comes off the pump the first time you fill a hired or new motor, say "diesel" aloud. Silly, yes, but it does the trick.
- Thinking about something else is when this becomes an easy mistake to make, so put the phone away and keep your mind on the petrol pump.
- Up to a point, a misfuel inhibitor helps: some diesels come with a filler built to block a petrol nozzle, and add-on devices are available for the remainder. Count it as a safety net, and keep checking the pump.
- Stop as soon as you realise. Less petrol in that tank makes a weaker mixture. It does not change what to do next, which is still not to crank it.
Butterrow: already put petrol in a diesel?
Then, there is just a short order of things. Don't turn the ignition on, and do not fire it up. If you're still on the forecourt — BP or anywhere else — ask the staff to help you push it away from the petrol pump. Next, 0333 366 0103. We'll ask what got in, about how much, and if it has been run.
If it was AdBlue rather than petrol, say so. That's a different issue — corrosion and deposits and not lost lubrication — and it has its own page for Butterrow.
Why one petrol in a diesel job around Butterrow costs more than another
The four situations above are four different jobs, so no single quote for this would be fair. What shifts your cost is mostly which of them you're in. The proportion matters next, meaning how much of your tank is petrol, and then the location of the car and whether reaching it is safe for a van.
Ahead of any quote, not after, we ask three queries: the fuel that got in, the quantity, and whether it has run. That's why. A range turns into a straight figure once the answers are in.
About Butterrow
Butterrow is a village situated on the riverside in Gloucestershire, with a mix of detached housing and a population of around 658 residents. Butterrow sits at an elevation of 108 metres, close to the nearby places of Bowbridge, Thrupp, and Bagpath. Butterrow is located near Gloucester, which is approximately 9.1 miles away, and is about 90.7 miles west of London. Butterrow remains a quiet residential community with a rural character.
Fuel drain cover around Butterrow and across Gloucestershire
Butterrow rests in the GL postcode area, and the vans that answer petrol in diesel call-outs there work the spots around it as well — Bowbridge, Thrupp and Bagpath among them. The car doesn't need to come to us: our technicians drain at a forecourt, in a supermarket car park, in a lay-by or on your own drive.
At the pump around Butterrow, still?
In that case, you couldn't be in a better position. Keep the car switched off, then ring.