Petrol in a Diesel Car in Great Tey: How Worried Should You Be?
Not started? Then less worried than you probably are. Petrol sitting in a diesel tank does nothing to your motor till something draws it through the fuel system — the ignition priming the pump, your starter, or driving on its own. So the honest answer to the first query anyone in Great Tey asks, "have I wrecked it?", is normally no. To leave the vehicle like that, phone Petrol in Diesel and leave your engine switched off. Below, 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 motor: what petrol in a diesel does
On its way through an engine, diesel does two jobs. It protects to begin with, and after that does it burn. What stops the surfaces inside the high-pressure fuel pump and your injectors from wearing 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. A pump running on a petrol blend is wearing itself out, since petrol is runnier than diesel and takes away the protection the fuel system relies on. Petrol is also made to resist igniting under compression — the reverse of what a diesel needs from its fuel — and that's where any rattling starts.
Put these together and the shape of the issue is clear. Contact doesn't do the damage — movement does. Where the petrol is only in that tank, it is an issue of fuel, nothing more. Whatever a worn pump sheds goes on, borne 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 issue starts.
Four situations our engineers see in Great Tey: how serious is petrol in a diesel?
Fuelled up, not once started. The best case there can be. Just your tank has petrol in it, so the job is draining that tank and purging your system where the car stands. This scenario can only truly take place on a forecourt: anywhere else, the vehicle got there by being driven.
Started for a moment, or only the ignition on. Once primed, the system has drawn petrol out of that tank as far as the filter and the fuel lines. That is usually still an easy job — a drain, a flush, and your filter dealt with.
A few miles driven, and your pump has spent each of them labouring on weakened fuel. Tank, lines, filter, then clean fuel put through the entire circuit: that is this work, and the way the vehicle was driven counts as much as the mileage. On the school run to Great Tey Church of England Voluntary Controlled Primary School, the mileage is small. Very different again: a run to Colchester, under 10 miles away, or any mileage on the M11, under 25 miles from Great Tey, where the motor never stopped labouring hard.
It protested, and only then stopped: smoke, rattling, a throttle gone soft, an idle gone lumpy. The fuel isn't acting like diesel any more, and the engine is saying so. Pull up wherever you are — the verge on Moor Road, a lay-by, a side street — and leave it there. A vehicle pulled over soon very seldom has long-term damage, because the drain and the flush-through, which still go first, take care of it.
Myths Great Tey people hear about petrol in a diesel
Myth: "Fill it the rest of the way with diesel and it will be fine." It will not. A fuller tank of the same mix is all it gives, since topping up removes nothing. The idea behind that advice — that diesel fuel systems tolerate petrol by percentage — is wrong.
Myth: "A newer diesel can cope with a bit of petrol." If anything, the opposite. Protection matters more on current diesels, not less, because their fuel runs through finer components at higher pressure.
Myth: "If it starts and drives, there is no harm done." This is the one that fools people. The driver of a petrol engine fed diesel usually has no choice but to stop, because it will not run, and the harm stops there. Nothing seems to have happened when a diesel fed petrol fires up, ticks over and drives away, which it usually does; meanwhile the pump wears. Running does not mean fine.
Myth: "Add some two-stroke oil and drive the vehicle home." It's an old fix for a different fault. It doesn't put back what petrol has thinned, and the petrol is still inside the tank afterwards.
"Drain it yourself and you're sorted" — a myth, because after it has been running some petrol sits in the filter and lines, waiting to go straight back through your pump at the next start. Besides, petrol cleared into a can by the road is truly risky.
How petrol ends up: petrol in a diesel
On purpose? Never. Through carelessness? Seldom, if ever. One way only, because of the nozzles: the smaller petrol one slips inside a diesel filler with almost no resistance, whereas the diesel one mostly won't fit a petrol motor. That's how the forecourt makes it straightforward.
Routine and the car getting out of step is when it takes place. Courtesy car, hire car, or a motor that's brand new. A household with one petrol and one diesel on the driveway. Your ordinary forecourt, its pumps now in a different order. Filling up in a hurry en route to Chappel & Wakes Colne, with a train to catch. The first fill-up in a diesel Volkswagen Golf after years of driving petrol is exactly the moment it takes place. Add rain, a phone call or a back seat full of children, and your hand repeats what it has always done.
Next time you fill up around Great Tey: preventing petrol in a diesel
- Check the pump, not the colour. In the UK unleaded handles are usually green and diesel black, but not on each forecourt. The label is what counts.
- The first fill in a strange car is the time to check your filler flap — inside it, or on the cap, many motors state the fuel to use.
- One of each in the household? Mark the key to the diesel — a coloured fob, a sticker — because intending to remember isn't enough.
- It sounds daft and it works: on the first fill in a new or hired car, say "diesel" aloud before you take the nozzle off the petrol pump.
- Thinking about something else is when this becomes an easy mistake to make, and so put your phone away then keep your mind on the petrol pump.
- Some diesels come with a filler designed to refuse a petrol nozzle, and devices you can add exist for cars without one. Such an inhibitor helps up to a point — as a backstop, not a reason to stop reading the petrol pump.
- Less petrol means a thinner blend, and so stop as soon as you notice — though remembering that the next stage is unchanged. It is still not to fire it up.
Already put petrol in a diesel in Great Tey?
Short and simple, then, is the order of things. Starting it is out, and so is switching on the ignition. If you're still on the forecourt — Shell or anywhere else — ask the staff to help you push it clear of the pump. Ring 0333 366 0103 next, with three facts — the fuel, the approximate amount, and whether it has run.
If it was AdBlue and not petrol, say so. That's a different problem — corrosion and deposits rather than lost protection — and it has its own page for Great Tey.
What makes one Great Tey petrol in a diesel job cost more than the next
An honest single price doesn't exist here: four situations, four separate jobs. Which of them you are in is mostly what moves the cost. After that it's the share — how much petrol got in against how much the tank holds — and then where the vehicle is and whether our van can reach it safely.
What got in, how much, and if it's run — three questions our engineers ask before pricing, not after, for exactly that reason. A range becomes a straight figure once those replies are in.
About Great Tey, briefly
Great Tey is a small village in Essex, situated approximately 6.5 miles from Colchester and 46.3 miles from London. Great Tey sits in a rural area at an elevation of around 62 metres, with nearby places including Swan Street, Chappel, and East Gores. Great Tey has a population of around 608 people and is characterised by predominantly detached housing.
Great Tey and Essex: where our fuel drain cover runs
Petrol in diesel jobs around Great Tey — part of the CO postcode area — go to teams that likewise cover the spots about it, Swan Street, Chappel and East Gores included. A forecourt, a supermarket car park, a lay-by or your own drive are all places our technicians work, and your car doesn't need to move to us.
Still at the pump around Great Tey?
No position is better: that is where you are. Leave the vehicle switched off, then ring.