Petrol in a Diesel Car in Dilton Marsh: How Worried Should You Be?
Probably less than you are now — provided nobody has started the car. Petrol resting in a diesel tank does nothing to your engine until something draws it through your fuel system — your ignition priming your pump, your starter, or driving on its own. So the honest answer to the first query anyone in Dilton Marsh asks, "have I wrecked it?", is usually no. Petrol in Diesel is who to ring, with the engine left 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 a second time.
What petrol in a diesel does to your engine
Diesel has two jobs on its way through a motor. It protects first, and after that does it burn. What keeps the surfaces inside your high-pressure pump and the injectors from wearing down against each other is the diesel passing through them — they're built to extremely fine clearances.
Of these two tasks, petrol handles the first poorly and the second not at all. The knocking comes from petrol being made not to ignite when compressed, which is exactly the reverse of what a diesel needs. On top of that it is thinner than diesel, it strips away the protection the system hinges on, and any pump working on such a blend is wearing itself.
The shape of the trouble is plain when you put those together. The harm is done by circulation, not by contact. Where the petrol is only inside that tank, it is a fault of fuel, nothing more. The start of a mechanical problem is a pump that has been labouring on that petrol — and whatever a worn pump sheds travels on with the fuel to the injectors beyond it.
Petrol in a diesel in Dilton Marsh: how serious is it? Four situations
Fuelled, and never started: no case is better. The petrol is inside the tank and only your tank, and the task is a drain and a flush where the vehicle stands. This is the one situation that can only really occur at a forecourt, because anywhere else your car has been driven to get there.
Ignition on, or started for a second. The system has been bled, so petrol has left the tank and got to your filter and the lines. Drain, flush, see to the filter: still normally straightforward.
Those few miles driven were the pump labouring on fuel thinned by petrol throughout. The work is that tank, the lines, the fuel filter and fresh fuel through the whole system, and how hard your car was driven counts as much as how far. Driving the children to Dilton Marsh CofE Primary School is one kind of trip. Very different once more: a run to Bath, under 15 miles away, or any mileage on the M4, under 25 miles from Dilton Marsh, where the motor never stopped working hard.
It complained, and only then stopped: smoke, rattling, a throttle gone soft, an idle gone ragged. What you are hearing is the engine signalling fuel that no longer acts like diesel. Pull up on the spot — on the verge on The Hollow, at the kerb, down a side road — and don't move it again. Long-term damage is very uncommon when a vehicle is stopped early, and the drain and flush-through that still come first take care of it.
What Dilton Marsh drivers get told about petrol in a diesel — and the stories in it
"Top it up the rest of the way with diesel and it'll be fine" — a myth. It will not. Topping up takes out nothing; it gives you a bigger tank of the same mix. Percentage is not how a diesel fuel system copes with petrol, however much that advice assumes.
"Newer diesels can handle a little petrol" — a myth, and nearer the opposite. A current diesel runs its fuel through smaller components at higher pressure, which makes the lubrication count more, not less.
Myth: "If it starts and drives, there is no damage done." This is the one that catches motorists. Feed diesel to a petrol motor and it normally will not run, and so the motorist stops — and the damage stops with them. A diesel fed petrol usually starts, idles and drives away as though nothing has happened, while your pump wears. Running does not mean fine.
An outdated fix for a separate fault lies behind this one. Myth: "Add some two-stroke oil and drive the vehicle home." It does not put back what petrol has weakened, and that petrol is still in that tank afterwards.
Once the engine has been run, part of that petrol sits in the filter and the fuel lines, not that tank — and the next start sends it right back through the pump. So the myth "drain your tank yourself and you are sorted" does not hold. It's also genuinely hazardous to drain petrol into a can by the kerbside.
How does petrol in a diesel take place?
No one does it on purpose, and it is rarely carelessness. The petrol nozzle is the narrower of the two and slides into a diesel filler with almost no resistance; a diesel nozzle generally won't go into a petrol car at all. The forecourt makes it simple, and the mistake runs one way.
When routine and the car stop matching, it occurs. A new car, a hire car or a courtesy car. A household with one petrol and one diesel on the drive. A well-known forecourt with the pumps in a different order. A hurried fill on the way to the nearest station with a train to catch. A new-to-you diesel Volkswagen Golf, its first fuelling, and a motorist used to petrol: precisely when it occurs. Add rain, a phone call or a back seat full of kids, and your hand repeats what it has always done.
How to prevent petrol in a diesel on your next fill-up in Dilton Marsh
- Read the petrol pump, not the colour. In the UK unleaded handles are normally green and diesel black, but not on every forecourt. The label is what counts.
- Inspect the filler flap. Plenty of cars state the fuel type inside the flap or on the cap. Look at it on the first fill in any vehicle you don't know.
- One of each in the household? Label your key to the diesel — a coloured fob, a sticker — because meaning to remember is not enough.
- It sounds silly and it does the trick: on the first fill in a new or hired car, say "diesel" out loud before you lift the nozzle off the petrol pump.
- Whilst you're thinking about something else, this is an easy mistake to make — so tuck the phone away.
- A misfuel inhibitor helps, up to a point. Some diesels come with a filler built to refuse a petrol nozzle, and add-on devices exist for motors without one. They are a safety net, not a reason to stop checking the petrol pump.
- Stop the moment you realise. Less petrol in the tank means a weaker blend. It does not change what to do next, which is still not to crank it.
Petrol already in a diesel around Dilton Marsh? Start here
The order of things is brief, then. Don't switch the ignition on, and don't fire it up. The staff on the forecourt — whether at Esso itself or wherever you filled up — will normally help push it away from the pump if you ask. Then call 0333 366 0103 and tell us what got in, roughly how much, and whether it has run.
Corrosion and deposits form the trouble with AdBlue, where petrol means lost protection. So if it was AdBlue, say so — and see its own Dilton Marsh page.
What makes one Dilton Marsh petrol in a diesel job cost more than the next
The four situations above are four different jobs, so no single quote for this would be honest. The situation itself does most of the work of moving the cost. Two things follow that: the petrol that got in as a share of what your tank holds, then the place the car is in and whether our van can reach it safely.
That's why we ask three queries before pricing rather than after: what was put in, how much, and if it has run. Those answers are what change a range into one firm number.
About Dilton Marsh
Dilton Marsh is a village in Wiltshire, situated inland at an elevation of around 80 metres, approximately 11 miles from the city of Bath. Dilton Marsh has a population of around 1289 people and is characterised by predominantly detached housing. Dilton Marsh is located near other small places such as Penknap, Hisomley, and Penleigh, and is about 92 miles west of London.
Dilton Marsh and Wiltshire: where our fuel drain cover reaches
Petrol in diesel call-outs in Dilton Marsh — part of the BA postcode area — go to teams that likewise cover the locations about it, Penknap, Hisomley and Penleigh among them. No need to bring the vehicle to us. Forecourts, supermarket car parks, lay-bys and your own driveway are all places where we work.
Still at the pump in Dilton Marsh?
Then, you couldn't be in a better place. Leave the car turned off, and ring.