How Worried Should You Be? Petrol in a Diesel Car in Ynyshir
If it hasn't been started, you can worry less than you likely are. Petrol sitting in a diesel tank does nothing to the motor until something draws it through your fuel system — the ignition priming your pump, your starter, or the drive on its own. So the honest answer to the first question anyone around Ynyshir asks, "have I ruined it?", is normally no. Leave your engine off then phone Petrol in Diesel — that keeps it like that. Keep reading for three things: the effect petrol has inside a diesel engine, the clues of how far it has spread, and the way to make sure you don't do it again.
What petrol in a diesel does to the engine
Diesel has two tasks on its way through an engine. Before it ignites, it protects — and then it ignites. Very fine clearances are built into your injectors and the high-pressure pump, and just your diesel flowing through keeps those surfaces from grinding together.
Petrol does the first job poorly and the second not at all. Being less viscous than diesel, petrol strips away the lubrication a fuel system needs, so a pump running on the mixture wearing itself. It is also made to resist igniting under compression — the reverse of what a diesel needs — which is why you get the rattling.
Taken together, they make clear the shape the problem takes. Contact doesn't do the harm — movement does. A tank with petrol in it is a fuel fault. The beginning of a mechanical one is a pump that has been working on that petrol — and whatever a worn pump sheds moves on with your fuel to the injectors beyond it.
Petrol in a diesel in Ynyshir: how serious is it? Four cases
Filled up, and never started: nothing beats it. Just your tank has petrol in it, so the job is emptying the tank and cleaning the fuel system where the car sits. This situation can only truly occur on a forecourt: anywhere else, your car got there by being driven.
Your ignition turned on, or a short start. Petrol has come out of the tank and got to the fuel filter and the lines, because the fuel system has been primed. Drain, flush, see to your filter: still normally straightforward.
Driven a few miles. Now the pump has spent those miles labouring on diluted fuel. How hard the vehicle was driven counts as much as how far, and the work covers your tank, the lines, your filter and clean fuel through the entire system. Driving the children to the local primary school is one kind of trip. Any distance on the M4, under 10 miles from Ynyshir, means the motor working hard throughout, and a run to Cardiff, under 15 miles away, is a very different task as well.
It complained, and only then stopped: smoke, rattling, a throttle gone soft, an idle gone lumpy. The engine is telling you your fuel is no longer behaving like diesel. Leave it wherever it stops: a lay-by, a side street, the verge on South Street. What goes first is still the drain and flush, and that takes care of it, with lasting damage very uncommon if a car is stopped quickly.
Myths Ynyshir drivers hear about petrol in a diesel
It will not be fine. The myth: "Fill it the rest of the way with diesel and it will be." Nothing is removed by topping up — you're left with a fuller tank, still the same mixture. A diesel fuel system does not accept petrol by percentage in the way that advice assumes.
"Newer diesels can handle a little petrol" — a myth, and nearer the reverse. At higher pressure, through smaller components: that's how a current diesel handles its fuel, and so the lubrication matters more, not less.
Myth: "If it starts and drives, there's no damage done." This is the one that fools drivers. The driver of a petrol motor fed diesel usually stops, since it will not run, and the harm stops there. Feed petrol to a diesel and it normally starts, idles and drives away like nothing happened — all while its pump is wearing. Running doesn't mean fine.
An outdated fix for a separate fault is behind this one. Myth: "Add some two-stroke oil and drive the car home." What petrol has weakened remains weakened, and that petrol stays in that tank anyway.
"Drain it yourself and you are sorted" — a myth, because after it has been running some petrol sits in the fuel filter and lines, waiting to go straight back through your pump on your next start. Emptying petrol into a can at the roadside is also really hazardous.
Petrol in a diesel: how does it occur?
It's rarely carelessness, and no one does it on purpose. The petrol nozzle is the slimmer of the two and slips 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.
The moment routine stops matching the vehicle is the moment it takes place. Any vehicle that's new to you — hired, on loan as a courtesy car, or brand new. A household with one petrol and one diesel on the driveway. The pumps in a different order on a familiar forecourt. A train to catch, and a rushed fill en route to Porth. The first fill-up in a diesel Volkswagen Passat after years of driving petrol is exactly the moment it occurs. With rain, a call arriving, or children to deal with, the hand simply does what it always has.
Ynyshir motorists: how to prevent petrol in a diesel next time
- The label is what counts, so check the pump rather than the colour: in the UK unleaded handles are usually green and diesel black, yet not on each forecourt.
- The first fill in a strange motor is the time to check the filler flap — on it, or on the cap, plenty of motors state which fuel they take.
- Good intentions do less than a sticker or a fob in a vivid colour on the diesel's key if a home has one of each. So label it.
- Before the nozzle comes off the petrol pump the first time you fill a hired or new vehicle, say "diesel" aloud. Silly, perhaps, but it does the trick.
- While you're thinking about something else, this is an easy mistake to make — so tuck your phone away.
- A misfuel inhibitor helps, up to a point. Some diesels come with a filler built to reject a petrol nozzle, and add-on devices exist for motors without one. They are a backstop, not a reason to stop reading the petrol pump.
- Spotting it halfway? Stop there and then. A weaker mixture follows from less petrol inside the tank, but your next stage remains the same: do not fire it up.
Put petrol in a diesel in Ynyshir already?
In that case, there's just a short order of things. Leave it unstarted, with your ignition off too. The staff at the forecourt — whether at Texaco itself or wherever you filled up — will usually help roll it away from the pump if you ask. Then phone 0333 366 0103 and tell us what went in, roughly how much, and whether it has run.
Say so if it was AdBlue instead of petrol: it is a different problem, with its own page for Ynyshir, since AdBlue brings corrosion and deposits rather than lost protection.
What makes one Ynyshir petrol in a diesel job cost more than the next
The four situations above are four separate jobs, so no single quote for this would be fair. What shifts your cost is chiefly which of them you're in. The ratio counts next, meaning how much of that tank is petrol, and then the position of the car and whether getting to it is safe for a van.
What went in, how much, and whether it has run — three queries we ask before pricing, not after, for precisely that reason. Given the replies, you get a straight figure instead of a range.
About Ynyshir, briefly
Ynyshir is a suburban area situated on the banks of the River Rhondda in south Wales, with a mix of terraced housing and local amenities. Ynyshir sits at an elevation of around 118 metres, near the communities of Mount Pleasant and Birchgrove. Ynyshir is located close to the larger town of Wattstown and is approximately 14 miles from Cardiff, the capital city of Wales.
Fuel drain cover around Ynyshir and across Rhondda Cynon Taf
Ynyshir rests in the CF postcode area, and the vans that answer petrol in diesel jobs there work the spots near it as well — Mount Pleasant, Birchgrove and Wattstown among them. Our engineers drain wherever your vehicle is — your own driveway, a lay-by, a supermarket car park, a forecourt — so it does not have to come to us.
At the pump around Ynyshir, right now?
The best place there is, then — that's where you are. Ring, and keep it switched off.