How Worried Should You Be? Petrol in a Diesel Car in North Mundham
Likely less than you already are — as long as no one has started the car. Till the ignition primes your pump, the starter cranks, or your vehicle is driven, petrol in a diesel tank simply sits there and does nothing. Which means the truthful reply to that first North Mundham question — "have I wrecked it?" — usually no. Petrol in Diesel is who to call, with the motor kept off, so it stays that way. Further down, you will find what petrol actually does inside a diesel, how far it might have got, and how to stop it happening to you again.
Inside the engine: what petrol in a diesel really does
On its way through an engine, diesel has two tasks. It ignites, and before it burns it protects. Designed to very fine tolerances, the fuel injectors and the pump depend on the diesel moving through them to stop their surfaces wearing against one another.
Badly at the first, not at all at the second: that is petrol. A pump working on a petrol blend is wearing itself out, because petrol is runnier than diesel and takes away the lubrication your fuel system relies on. Petrol is also designed to resist igniting under compression — the opposite of what a diesel wants from its fuel — and that's where any clattering comes.
The shape of the problem is clear once you put those together. Not contact but circulation is what does the harm. All a tank with petrol in it amounts to is a fuel problem. The beginning of a mechanical one is a pump that has been running on that petrol — and whatever a worn pump sheds travels on with the fuel to your injectors downstream.
Four scenarios our engineers see in North Mundham: how bad is petrol in a diesel?
Filled up, not once started. The best case there is. Just your tank has petrol in it, and so the task is clearing that tank and cleaning the system where your car sits. This scenario can only truly happen on a forecourt: anywhere else, the car got there by being driven.
Started for a second, or just your ignition on. Petrol has left your tank and reached the filter and your lines, because the system has been primed. Drain, flush, see to your filter: still usually easy.
Those few miles on the road were your pump working on fuel thinned by petrol the whole way. Mileage is only half of it; how hard it was driven counts just as much. Either way the work includes that tank, the lines, your filter and clean fuel through the entire circuit. The school run to North Mundham Primary School is one matter. Any miles on the Waterlooville Bypass, under 15 miles from North Mundham, means your engine working hard throughout, and a run to Chichester, under 3 miles away, makes a very different task as well.
Driven on until it complained — clattering, smoke, an uneven idle, a dead throttle. The engine is telling you your fuel is no longer behaving like diesel. Pull up where you are — on the verge on B2166, at the kerb, down a side road — and don't move it. A vehicle pulled over soon very seldom has long-term damage, as the fuel drain and the flush-through, which still come first, take care of it.
North Mundham motorists and that petrol in a diesel stories they hear
"Top it up the rest of the way with diesel and it'll be fine" — a myth. It will not. Nothing is removed when you top up — that tank just holds more of the same blend. Percentage is not how a diesel fuel system tolerates petrol, however much that guidance assumes.
Myth: "A current diesel can cope with a bit of petrol." If anything, the reverse. Protection counts more on modern diesels, not less, since their fuel runs through smaller parts at higher pressure.
This is the one that fools people. Myth: "If it starts and drives, there is no harm done." The driver of a petrol engine fed diesel normally stops, since it will not run, and the harm stops with them. Whilst your pump wears, a diesel fed petrol usually starts, idles and drives away as if nothing has happened. Running isn't the same as fine.
An old fix for a distinct problem lies behind this one. Myth: "Add some two-stroke oil and drive the car home." The petrol is still in the tank afterwards, and what it has weakened isn't put back.
"Drain it yourself and you're sorted" — a myth, because after it has been running some petrol lies in the fuel filter and lines, ready to go straight back through the pump at the next start. On top of that, petrol emptied into a can by the road is truly risky.
How it happens: petrol in a diesel
Carelessness is rarely the cause, and no one means to do it. One way only, because of the nozzles: the smaller petrol one slides inside a diesel filler with almost no resistance, while the diesel one mostly will not fit a petrol car. That's how the forecourt makes it simple.
The moment habit stops matching the car is the moment it occurs. A new vehicle, a hire car or a courtesy car. A household with one petrol and one diesel on the drive. Your usual forecourt, its pumps now in a different order. A train to catch, and a rushed fill on the way to Chichester. Years of petrol cars behind you, a diesel Renault Megane in front of you on the forecourt for its first tank — that's when. Add rain, a phone call or a back seat full of children, and the hand repeats what it has always done.
Next time you fill up in North Mundham: avoiding petrol in a diesel
- The label is what counts, so read the petrol pump rather than the colour: in the UK unleaded handles are normally green and diesel black, but not on every forecourt.
- Inspect your filler flap. Many motors state the fuel inside the flap or on the cap. Look at it on your first fill in a car you do not know.
- A coloured fob or a sticker on the diesel's key achieves more than any amount of intending to remember, in a home with one of each.
- It seems daft 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.
- Put your phone away. This is an easy mistake to make while you are thinking about something else.
- Up to a point, a misfuel inhibitor helps: some diesels come with a filler designed to reject a petrol nozzle, and aftermarket devices exist for the remainder. Count it as a safety net, then keep reading the pump.
- The moment you realise, stop: less petrol inside the tank makes a thinner blend. What to do next does not change, though — still do not fire it up.
Already put petrol in a diesel around North Mundham?
Short and simple, then, is the order of things. Starting it is out, and so is switching on the ignition. Yet on the forecourt, at Esso or anywhere else? Ask the attendants to help you roll it away from the pump. Phone 0333 366 0103 next, with three answers — your fuel, the approximate volume, and whether it's run.
AdBlue, not petrol? Then say so. Corrosion and deposits, not lost protection, make it a different fault — North Mundham has a page just for it.
One petrol in a diesel task around North Mundham costs more than another. Why?
The four situations above are four separate tasks, so no single quote for this would be fair. Chiefly, the cost moves with which one you're in. The proportion matters next, meaning how much of that tank is petrol, and then the position of the car and whether reaching it is safe for a van.
Before any quote, not after, we ask three queries: your fuel that went in, the amount, and whether it's run. That is why. A range becomes a straight figure when those answers are in.
About North Mundham, briefly
North Mundham is a village in West Sussex, situated near the coast and close to the city of Chichester. North Mundham lies at a low elevation of around 6 metres, and its population of approximately 1196 people live in predominantly detached housing. North Mundham is surrounded by nearby places such as Runcton, Hunston, and Woldhurst, and is within a short distance of the South Downs National Park. North Mundham benefits from its proximity to Chichester, which provides access to a range of amenities and services.
Fuel drain cover around North Mundham and across West Sussex
The teams answering petrol in diesel call-outs in North Mundham, in the PO postcode area, also work the places near it, Runcton, Hunston and Woldhurst among them. No need to move the vehicle to us. Forecourts, supermarket car parks, lay-bys and your own driveway are all locations where we work.
North Mundham: still at the petrol pump?
The best place there is, then — that is where you are. Phone, and leave it turned off.