Should You Worry? Petrol in a Diesel Car in Princes Marsh
Less than you probably are, if it hasn't been started. "Have I wrecked it?" is the first thing anyone in Princes Marsh asks, and the truthful answer is generally no, since petrol left in a diesel tank hurts nothing till it is drawn through the system — by ignition priming, by the starter, or by driving. Keep it that way: leave the engine off and ring Petrol in Diesel. What petrol actually does to a diesel, how to gauge how far it's travelled, and how to stop it from happening again: that's the remainder of this page.
What petrol in a diesel does to the engine
Diesel does two tasks on its way through an engine. Before it burns, it protects — then it combusts. The high-pressure fuel pump and the injectors are built to extremely fine tolerances, and the diesel passing through them is what keeps those surfaces from wearing against one another.
The second job petrol doesn't do at all, and the first it does poorly. The rattling comes from petrol being designed not to ignite when compressed, which is exactly the opposite of what a diesel needs. On top of that it is thinner than diesel, it strips away the lubrication the system depends on, and any pump running on that blend is wearing itself.
Seen together, they make clear what shape the problem takes. The harm is done by circulation, not by contact. Where that petrol is only inside that tank, it is an issue of fuel, nothing more. Whatever a worn pump sheds travels on, borne by the fuel, into the injectors further along, which is why a pump that has been working on the petrol is where a mechanical problem starts.
Princes Marsh, petrol in a diesel: four situations, from mild to serious
The best case there is: filled up, not once started. Being on a forecourt is what makes this possible: elsewhere, the vehicle has been driven there to begin with. With that petrol held in your tank alone, it's drained and cleaned on the spot, and nothing more is needed.
Ignition on, or started for a second. Your system has been primed, so petrol has left your tank and got to the filter and the fuel lines. Drain, flush, deal with your filter: still normally straightforward.
The pump has spent a couple of miles on thinned fuel — that is what driving it does. Tank, lines, filter, then fresh fuel put through the entire system: that's the work, and the way your car was driven counts as much as the miles. A school run to Liss Junior School is one thing. A run as far as Chichester, under 15 miles away, is a very different job. So is any miles on the Waterlooville Bypass, under 10 miles from Princes Marsh, where the engine has been working hard the whole time.
Driven on until it protested — rattling, smoke, a ragged idle, a dead throttle. What you are hearing is the engine signalling fuel that no longer behaves like diesel. Leave it where it stops: a lay-by, a side street, the verge on Upper Mount. Long-term damage is very rare if a vehicle is pulled over early, and the drain and flush that still go first sort it out.
Myths Princes Marsh people 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 are left with a bigger tank, still the same mixture. The idea behind the advice — that diesel fuel systems tolerate petrol by percentage — is wrong.
Not so: a modern diesel copes with a bit of petrol. If anything, the opposite. Finer components and higher pressure are how a modern diesel runs its fuel, and that makes the protection count more, not less.
One myth that catches drivers off guard: if it starts and drives, it must be unharmed. Feed diesel to a petrol engine and it usually will not run, and so the motorist stops — and the damage stops with them. While your pump grinds, a diesel fed petrol normally starts, ticks over and drives away as if nothing has happened. Running isn't the same as fine.
Myth: "Add some two-stroke oil and drive the vehicle home." It is an old workaround for a separate problem. What petrol has weakened remains weakened, and that petrol stays in the tank anyway.
"Drain it yourself and you are sorted" — a myth, because after it has been running some petrol lies in your filter and lines, waiting to go right back through your pump on your next start. It is also really risky to drain petrol into a can at the kerbside.
Why petrol in a diesel takes place at all
It's rarely carelessness, and no one does it on purpose. A diesel nozzle mostly will not go into a petrol motor, yet the smaller petrol nozzle goes into the filler of a diesel almost without resistance — so forecourts make this one mistake simple, and only in one direction.
The moment routine stops matching the vehicle is the moment it occurs. Hire cars, courtesy cars, and cars that are new to you. One petrol and one diesel on the driveway of the same household. The pumps in a different order on a well-known forecourt. Fuelling up in a hurry en route to Liss, with a train to catch. A new-to-you diesel Volkswagen Passat, its first fuelling, and a driver used to petrol: exactly when it happens. Your hand repeats what it has always done when you add rain, a phone call or a back seat full of children.
Preventing petrol in a diesel next time you fill up around Princes Marsh
- Check the pump, not the colour. In the UK unleaded handles are normally green and diesel black, yet not on each forecourt. The label is what counts.
- Check the filler flap. Many vehicles state the fuel type inside the flap or on the cap. Look at it on the first fill in a vehicle you don't know.
- Good intentions do less than a sticker or a fob in a bright colour on the diesel's key when a home has one of each. So mark it.
- It sounds silly and it does the trick: on the first fill in a new or hired car, say "diesel" aloud before you take the nozzle off the pump.
- Mistakes like this are simple to make while your mind is on something else, and so your phone goes away.
- Some diesels come with a filler built to refuse a petrol nozzle, and devices you can add are available for motors without one. Such an inhibitor helps up to a point — as a safety net, not a reason to stop reading the petrol pump.
- As soon as you realise, stop: less petrol in your tank makes a weaker mix. What to do next doesn't change, though — still don't start it.
Petrol already in a diesel in Princes Marsh? Start here
Short and simple, then, is the order of things. Starting it is out, and so is switching on your ignition. The staff on the forecourt — whether at Esso itself or wherever you filled up — will normally help roll it away from the petrol pump if you ask. Then phone 0333 366 0103 and tell us what got in, roughly how much, and if it's run.
Say so if it was AdBlue rather than petrol: it is a separate fault, with its own page for Princes Marsh, because AdBlue brings corrosion and deposits instead of lost lubrication.
One petrol in a diesel job in Princes Marsh costs more than another. Why?
The four situations above are four different jobs, so no single quote for this would be honest. Mostly, your cost shifts with which situation you are in. Two things come after that: the petrol that got in as a proportion of what your tank takes, then the place the vehicle is in and whether a van can get to it safely.
What went in, how much, and whether it has run — three questions our engineers ask before pricing, not after, for exactly that reason. A range becomes a straight figure once those answers are in.
About Princes Marsh itself
Princes Marsh is a suburban area situated on the riverside in Hampshire, with an elevation of around 65 metres. Princes Marsh lies near the cities of Chichester and Portsmouth, and is close to the villages of Liss, East Hill, and Lower Green. Princes Marsh has a population of approximately 1123 residents, living in predominantly semi-detached housing. Princes Marsh is located within commuting distance of London, at around 46 miles from the capital.
Across Hampshire and in Princes Marsh: fuel drain cover
Our teams answering petrol in diesel calls in Princes Marsh, in the GU postcode area, also work the places around it, Liss, East Hill and Lower Green included. The vehicle does not need to move to us: our engineers drain at a forecourt, in a supermarket car park, in a lay-by or on your own driveway.
In Princes Marsh and still at the pump?
Then you are in the best position there is. Keep it turned off, then ring.