Petrol in a Diesel Car in Bevois Valley: How Worried Should You Be?
Likely less than you already are — provided nobody has started the car. Petrol resting in a diesel tank does nothing to the engine till something pulls it through the system — the ignition priming the pump, your starter, or the drive on its own. So the honest answer to the first question anyone around Bevois Valley asks, "have I wrecked it?", is normally no. Keep it that way: leave the motor off and ring Petrol in Diesel. Keep reading for three things: the effect petrol has inside a diesel motor, the signs of how far it has spread, and the way to make sure you don't repeat it.
What petrol in a diesel does to your engine
Diesel has two jobs on its way through an engine. It ignites, and before it burns it lubricates. Very fine gaps go into the fuel injectors and the high-pressure pump, and just the diesel running through keeps their surfaces from grinding together.
The second job petrol does not do at all, and the first it does poorly. It's thinner than diesel and removes the protection your fuel system depends on, 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's where the rattling comes from.
Put those together and the shape of the trouble is clear. The harm is done by circulation, not by contact. Where that petrol is only in that tank, it's a fault of fuel, nothing more. Whatever a worn pump sheds goes on, carried by the fuel, into your injectors downstream, which is why a pump that has worked on the petrol is where a mechanical issue starts.
How serious is petrol in a diesel? Four scenarios our technicians see in Bevois Valley
The best case there is: filled up, not once started. Being at a forecourt is what makes this the case: elsewhere, the car has been driven there to begin with. With that petrol kept inside your tank alone, it is emptied and flushed right where it stands, and nothing more is needed.
Your ignition switched on, or a brief start. Petrol has left that tank and reached your filter and the fuel lines, since your system has been primed. Drain, flush, see to the fuel filter: still usually easy.
A couple of miles driven, and the pump has spent each of them running on thinned fuel. The work is the tank, the fuel lines, the filter and fresh fuel through the whole system, and how hard the vehicle was driven counts as much as how far. On the school run to Bevois Town Primary School, the miles is short. Driving as far as Southampton, under 3 miles away, makes a very different job — as does any mileage on the M27, under 3 miles from Bevois Valley, with the motor labouring hard the whole time.
Driven on till it complained — clattering, smoke, a ragged idle, a soft throttle. The engine is telling you your fuel is no longer behaving like diesel. Stop wherever you are — the verge on Thomas Lewis Way, a lay-by, a side street — then 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, long-term damage is very unusual.
What Bevois Valley people get told about petrol in a diesel — and the myths in it
It will not be fine. The myth: "Fill it the rest of the way with diesel and it'll be." Topping up takes out nothing; it gives you a bigger tank of the same mix. Percentage isn't how a diesel fuel system tolerates petrol, whatever that advice presumes.
"Current diesels can handle a little petrol" — a myth, and nearer the reverse. At higher pressure, through more precise parts: that is how a modern diesel handles its fuel, and so the protection counts for more, not less.
Myth: "If it starts and drives, there's no damage done." This is the one that catches people. The driver of a petrol engine fed diesel usually stops, because it will not run, and the harm stops there. Feed petrol to a diesel and it normally starts, idles and pulls away as if nothing happened — all while its pump is wearing. Running isn't the same as fine.
An outdated fix for a different problem lies behind this one. Myth: "Add some two-stroke oil and drive it home." None of what petrol weakened is put back by it — and afterwards, that tank still contains that petrol.
If your engine has been run, part of that petrol is in the filter and your lines, not your tank — and the next start pulls it straight back through the pump. So the myth "drain the tank yourself and you are sorted" does not hold. Draining petrol into a can at the roadside is also really dangerous.
Why petrol in a diesel happens so easily
A careless moment is rarely the cause, and nobody means to do it. 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 motor at all. The forecourt makes it easy, and the mistake runs one way.
It occurs when routine and the vehicle stop matching. Courtesy car, hire car, or a vehicle that is new. One petrol and one diesel on the driveway of the same household. A familiar forecourt with the pumps in a different order. A train to catch, and a rushed fill on the way to St Denys. Precisely the moment it takes place: after years of driving petrol, someone fills a diesel Renault Megane for the first time. Add a back seat full of children, a phone call or rain, and the hand wins.
Preventing petrol in a diesel next time you fill up around Bevois Valley
- Green for unleaded and black for diesel is normal in the UK — but not on every forecourt. Trust the label on the petrol pump, not the colour.
- In a vehicle you don't know, look inside the flap over your filler or at the cap before the first fill: many vehicles state the fuel there.
- A coloured fob or a sticker on the diesel's key does more than any amount of intending to remember, for a household with one of each.
- Say it before you lift it. On the first fill in a new or hired car, say "diesel" aloud before you take the nozzle off the petrol pump. It sounds daft and it works.
- Mistakes like this are straightforward to make whilst your mind is on something else, and so your phone goes away.
- Some diesels come with a filler designed to reject a petrol nozzle, and devices you can add exist for cars without one. Such an inhibitor helps up to a point — as a safety net, not a reason to stop reading the pump.
- Stop the moment you notice. Less petrol in that tank means a weaker mixture. It doesn't change what to do next, which is still not to start the vehicle.
Put petrol in a diesel around Bevois Valley already?
In that case, there is only a short order of things. Do not fire it up, and don't switch your ignition on. Yet at the forecourt, at Esso or anywhere else? Ask the staff to help you roll the vehicle away from the pump. Next, 0333 366 0103. We will ask what was put in, about how much, and if it's been run.
Say so if it was AdBlue rather than petrol: it is a different problem, with its own page for Bevois Valley, because AdBlue brings corrosion and deposits rather than lost protection.
What makes one Bevois Valley petrol in a diesel job cost more than the next
The four scenarios above are four different tasks, so no single price for this would be honest. The scenario itself does most of the work of moving your cost. Where the car is counts too, and whether a van can safely reach it, after the ratio of petrol to what your tank takes.
That's why our engineers ask three questions before quoting instead of after: what got in, how much, and if it has run. Those answers change a range into a straight figure.
About Bevois Valley
Bevois Valley is a suburban area located near the coast in southern Hampshire, sitting at an elevation of around 16 metres. Bevois Valley is close to the city of Southampton, with Bevois Town and Bevois Mount nearby. Bevois Valley has a high proportion of flat dwellings, reflecting its urban character. Bevois Valley is situated within the larger Southampton urban area, approximately 68 miles from London.
Bevois Valley and Hampshire: where our fuel drain cover reaches
Bevois Town, Bevois Mount and St Denys are among the spots near Bevois Valley that the same vans work, answering petrol in diesel calls across Bevois Valley's SO postcode area. A forecourt, a supermarket car park, a lay-by or your own driveway are all places our technicians drain, and the vehicle doesn't need to come to us.
In Bevois Valley and still at the petrol pump?
The best position there is, then — that's where you are. Turned off it stays; then phone.