Should You Worry? Petrol in a Diesel Car in Brynna
Provided it hasn't been started, you can worry less than you likely are. Till the ignition primes the pump, your starter cranks, or your car is driven, petrol in a diesel tank simply sits there and does nothing. Which makes the truthful reply to that first Brynna question — "have I ruined it?" — normally no. Petrol in Diesel is who to ring, with the motor left off, so it remains that way. The remainder of this page covers what petrol really does to a diesel, how to judge how far it has got, and how to make sure it does not happen to you again.
What petrol in a diesel does to your engine
Passing through an engine, diesel does two jobs at once. It combusts, and before it ignites it lubricates. Your high-pressure pump and your injectors are made to extremely fine gaps, and the diesel passing through them is what keeps those surfaces from wearing down against one another.
Of these two jobs, petrol handles the first badly and the second not at all. It's thinner than diesel and removes the lubrication the system rests on, and so a pump running on a petrol blend is a pump wearing itself. And petrol is designed to resist igniting under compression, which is the opposite of what a diesel needs from its fuel. That is where the clattering comes from.
Taken together, they show the shape the problem takes. Not contact but circulation is what does the harm. All a tank with petrol in it amounts to is a fuel fault. A pump that has been working on that petrol is the start of a mechanical one, and whatever a worn pump sheds moves on with your fuel to the fuel injectors downstream.
Brynna, petrol in a diesel: four cases, from mild to serious
The best case there can be: filled up, not once started. That petrol is inside that tank and only that tank, and the job is a drain and a flush where the car stands. This is the one scenario that can only truly happen on a forecourt, because anywhere else your car has been driven to get there.
The ignition switched on, or a short start. With the system primed, the lines and filter already hold petrol that has come from your tank. Still usually easy: drain, flush, and the filter dealt with.
Driven a few miles. Now the pump has spent those miles running on weakened fuel. How hard the car was driven counts as much as how far, and this work covers that tank, the fuel lines, your filter and fresh fuel through the whole circuit. Short trips, like the school run to the local primary school, are one matter. Very different again: a run to Cardiff, under 15 miles away, or any mileage on the M4, under 3 miles from Brynna, where the engine kept working hard.
Driven till it protested. Rattling, a lumpy idle, smoke, a throttle that has gone soft. That is the motor telling you its fuel no longer is acting like diesel. Whether it's the verge on Church Street, a lay-by or a side street, stop there and leave it. Long-term damage is very uncommon if a vehicle is pulled over soon, and the drain and flush that still come first deal with it.
What Brynna drivers get told about petrol in a diesel — and the myths in it
"Top it up the rest of the way with diesel and it will be fine" — a myth. It won't. Topping up removes nothing; it gives you a bigger tank of the same mixture. A diesel fuel system does not tolerate petrol by percentage in the way that guidance presumes.
Myth: a current diesel copes with a bit of petrol. Rather, the reverse. At higher pressure, through more precise components: that is how a current diesel handles its fuel, so the protection matters for more, not less.
"It starts, it drives, and so there is no harm" — the myth that trips up more motorists than any other. Feed diesel to a petrol engine and it usually will not run, so the motorist stops — and the harm stops with them. Nothing seems to have happened when a diesel fed petrol fires up, ticks over and drives away, as it usually does; meanwhile your pump wears. A running engine doesn't mean fine.
An old workaround for a separate issue is behind this one. Myth: "Add some two-stroke oil and drive it home." The petrol is still inside your tank after that, and whatever it has weakened is not put back.
The next start draws petrol back round your pump from the fuel lines and the filter, where some of it ends up once the motor has run. That is why a DIY tank drain doesn't leave you sorted — a myth. On top of that, petrol emptied into a can by the road is truly hazardous.
How petrol ends up: petrol in a diesel
It is rarely carelessness, and no one does it on purpose. The petrol nozzle is the narrower of the two and slips into a diesel filler with almost no resistance; a diesel nozzle mostly won't go into a petrol vehicle at all. The forecourt makes it easy, and the mistake runs one way.
It takes place when habit and the vehicle stop matching. A new motor, a hire car or a courtesy car. Households running one of each, petrol and diesel. A forecourt you know, only with its pumps arranged differently. A train to catch, and a hurried fill on the way to Llanharan. Years of petrol motors behind you, a diesel Volkswagen Golf in front of you at the forecourt for its first tank — that's when. With rain, a call coming in, or a car full of children to deal with, the hand simply does what it always has.
Brynna drivers: how to prevent petrol in a diesel next time
- Check the pump, not the colour. In the UK unleaded handles are usually green and diesel black, but not on each forecourt. The label is what matters.
- In a car you do not know, look inside the flap over your filler or at the cap before the first fill: plenty of motors print the fuel type there.
- Mark your key. In a home with one of each, a coloured fob or a sticker on your diesel's key does more than any amount of intending to remember.
- It seems daft and it does the trick: on your first fill in a new or hired car, say "diesel" aloud before you lift the nozzle off the pump.
- Mistakes like this are straightforward to make whilst your mind is on something else, so the phone goes away.
- Some diesels have a filler designed to reject a petrol nozzle, and devices you can add are available for cars without one. Such an inhibitor helps up to a point — as a backstop, not a reason to stop checking the petrol pump.
- Less petrol makes a thinner blend, so stop the moment you notice — though remembering that your next step is unchanged. It's still not to start it.
Already put petrol in a diesel in Brynna?
In that case, there's only a short order of things. Don't turn the ignition on, and don't fire it up. Still at the forecourt, at the nearest petrol station or anywhere else? Ask the attendants to help you roll the vehicle clear of the pump. Next, 0333 366 0103. We will ask what went in, about how much, and if it's been run.
AdBlue, not petrol? Then tell us. Corrosion and deposits, not lost protection, make it a different issue — Brynna has a page all for it.
Brynna petrol in a diesel jobs: why one costs more than another
The four situations above are four separate jobs, so no single quote for this would be fair. Which of them you are in is chiefly what moves the cost. Two things come after that: the petrol that was put in as a proportion of what the tank takes, then the place the car is in and whether a van can reach it safely.
Before any quote, not after, come three questions: your fuel that got in, the quantity, and whether it has run. That's why. A range becomes a straight figure once those replies are in.
About Brynna itself
Brynna is a village situated in the Rhondda Cynon Taf county of Wales, located near the riverside at an elevation of 83 metres. Brynna is close to the nearby villages of Bryncae and Brynnau Gwynion, and is approximately 13 miles from Cardiff. Brynna has a population of around 1202 people, predominantly living in semi-detached housing.
Across Rhondda Cynon Taf and around Brynna: fuel drain cover
Our teams answering petrol in diesel calls in Brynna, in the CF postcode area, also work the places around it, Bryncae, Brynnau Gwynion and Llanbad among them. A forecourt, a supermarket car park, a lay-by or your own driveway are all spots our engineers work, and your car doesn't need to move to us.
Still at the pump around Brynna?
The best spot there is, then — that's where you are. Leave it switched off, and ring.