Petrol in a Diesel Car in Ponciau: How Worried Should You Be?
Provided it hasn't been started, worry far less than you likely are. "Have I wrecked it?" is the first question anyone in Ponciau asks, and the honest answer is generally no, because petrol left in a diesel tank harms nothing until it's drawn through the system — by ignition priming, by your starter, or by being driven. Keep it that way: leave the motor off and phone Petrol in Diesel. Read on for three things: the effect petrol has inside a diesel engine, the signs of how far it has spread, and the way to make sure you don't do it again.
Inside the motor: what petrol in a diesel does
Passing through an engine, diesel does two jobs at once. Lubricating comes before burning; it does both. What stops the surfaces inside the high-pressure fuel pump and the fuel injectors from grinding against one another is your diesel flowing through them — they're built to extremely fine tolerances.
Poorly at the first, not at all at the second: that is petrol. Being less viscous than diesel, petrol strips away the protection a fuel system needs, so a pump running on the blend wearing itself. It is also made to resist igniting under compression — the opposite of what a diesel needs — which is why you hear the rattling.
Put these together and the shape of the trouble is plain. It's movement that does the harm, not contact. All a tank with petrol in it amounts to is a fuel issue. Whatever a worn pump sheds goes on, carried by the fuel, into the fuel injectors further along, which is why a pump that has been working on that petrol is where a mechanical fault begins.
Four situations our engineers see in Ponciau: how serious is petrol in a diesel?
Fuelled but never started — the best it gets. On a forecourt, and genuinely only there, the petrol is still confined to the tank — because everywhere else your car was driven to reach it. The task is emptying and rinsing on the spot.
A moment's running, or just your ignition on. With your system primed, the lines and filter now hold petrol that came from that tank. That is normally still a straightforward task — a drain, a flush, and the filter dealt with.
The pump has spent a couple of miles on thinned fuel — that is what driving it meant. The work is that tank, the fuel lines, the filter and clean fuel through the whole system, and how hard the vehicle was driven matters as much as how far. On the school run to the local primary school, the mileage is small. A run as far as Wrexham, under 5 miles away, is a very different task. So is any miles on the M53, under 25 miles from Ponciau, where your engine has been running hard the whole time.
Driven till it protested. Rattling, a lumpy idle, smoke, a throttle that has gone soft. The motor is telling you your fuel is no longer acting like diesel. Stop wherever you are — the verge on Walkers Lane, a lay-by, a side street — and leave the car where it is. The drain and flush-through still come first, and they deal with it: when a vehicle is stopped quickly, lasting damage is very unusual.
Stories Ponciau drivers hear about petrol in a diesel
Myth: "Fill it the rest of the way with diesel and it'll be fine." It will not. Nothing is removed by topping up — you are left with a fuller tank, still the same mixture. That guidance supposes a diesel fuel system tolerates petrol by percentage. It doesn't.
If anything, the reverse holds. Myth: "A modern diesel can cope with a bit of petrol." A modern diesel sends its fuel through more precise components at higher pressure, which makes the lubrication count more, not less.
Myth: "If it starts and drives, there's no damage done." This is the one that catches people. Feed diesel to a petrol motor and it generally won't run, so the motorist stops — and the damage stops with them. Feed petrol to a diesel and it usually starts, idles and drives away as if nothing has happened — all while its pump wears. Running isn't the same as fine.
"A drop of two-stroke oil and drive it home" — a myth, borrowed from a fix from years ago, for a distinct issue. None of what petrol diluted gets put back by it — and afterwards, your tank still contains that petrol.
"Drain it yourself and you are sorted" — a myth, because after it's been running some petrol sits in the filter and lines, ready to go straight back through your pump on your next start. Besides, petrol emptied into a can by the road is truly dangerous.
How does petrol in a diesel take place?
On purpose? Never. Through carelessness? Rarely, if ever. The forecourt makes it simple: the petrol nozzle is the narrower of the two, and it slides into a diesel filler with almost no resistance, whilst a diesel nozzle generally will not go into a petrol car at all. So the error runs one way.
When routine and the vehicle stop matching, it occurs. A new motor, a hire car or a courtesy car. One petrol and one diesel on the drive of the same household. A forecourt you know, only with its pumps laid out differently. Racing for a train at Ruabon and fuelling up en route. A new-to-you diesel Renault Clio, its first fuelling, and a driver accustomed to petrol: precisely when it occurs. Throw in rain, a phone call or a back seat full of kids, and the hand repeats what it has always done.
Ponciau people: how to prevent petrol in a diesel next time
- Green for unleaded and black for diesel is usual in the UK — yet not on each forecourt. Go by the label on the pump, not the colour.
- Many vehicles state the fuel inside the filler flap or on the cap, so check there on your first fill in a vehicle you don't know.
- A coloured fob or a sticker on the diesel's key does more than any amount of intending to remember, in a house with one of each.
- It seems silly and it works: on the first fill in a new or hired car, say "diesel" out loud before you take the nozzle off the petrol pump.
- Thinking about something else is when this becomes an easy mistake to make, so tuck your phone away and keep your mind on the petrol pump.
- Up to a point, a misfuel inhibitor helps: some diesels have a filler built to block a petrol nozzle, and add-on devices are available for the rest. Treat it as a safety net, then keep reading the petrol pump.
- Stop as soon as you notice. Less petrol in the tank makes a weaker mixture. It doesn't change what to do next, which is still not to crank it.
Already put petrol in a diesel in Ponciau?
The order of things is brief, then. Starting it is out, and so is switching on the ignition. The attendants on the forecourt — whether at BP itself or wherever you filled up — will usually help roll it clear of the petrol pump if you ask. Then ring 0333 366 0103 and tell us what got in, roughly how much, and whether it's run.
Say so if it was AdBlue rather than petrol: it is a different fault, with its own page for Ponciau, since AdBlue brings corrosion and deposits instead of lost protection.
One petrol in a diesel job around Ponciau costs more than another. Why?
There is no honest single price for this, because the four scenarios above are four separate jobs. Chiefly, your cost moves with which one you are in. The proportion matters next, meaning how much of your tank is petrol, and then the position of the car and whether getting to it is safe for a van.
That is why our engineers ask three queries before costing rather than after: what got in, how much, and if it's run. Those answers change a range into a straight figure.
About Ponciau and where it is
Ponciau is a suburban area located near Wrexham in northeast Wales, sitting at an elevation of 155 metres above sea level. Ponciau is characterized by its semi-detached housing stock and is situated close to nearby communities such as Rhosllanerchrugog and Pant. Ponciau is a relatively small but distinct residential community on the outskirts of Wrexham, with the city centre just 3.3 miles away.
Fuel drain cover across Wrexham, Ponciau included
Rhosllanerchrugog, Rhosllannerchrugog and Pant are among the places near Ponciau that the same vans work, answering petrol in diesel call-outs across Ponciau's LL postcode area. No need to bring the vehicle to us. Forecourts, supermarket car parks, lay-bys and your own drive are all places we drain.
Ponciau: still at the pump?
The best place there is, then — that is where you are. Leave the vehicle turned off, and ring.