Maybush: Petrol in a Diesel Car? How Worried to Be
Likely less than you already are — as long as nobody has started it. Petrol sitting in a diesel tank does nothing to the motor till something pulls it through the fuel system — the ignition priming your pump, the starter, or driving itself. So the fair answer to the first query anyone around Maybush asks, "have I ruined it?", is generally no. To keep the car that way, phone Petrol in Diesel and leave the engine alone. The remainder of this page explains what petrol really does to a diesel, how to tell how far it has got, and how to make sure it doesn't happen to you again.
Inside the engine: what petrol in a diesel does
Two jobs fall to diesel on its route through a motor. It burns, and before it combusts it lubricates. Extremely fine clearances are built into the fuel injectors and your high-pressure pump, and just the diesel running through keeps their surfaces from grinding together.
Petrol does the first job poorly and the second not at all. A pump working on a petrol mix is wearing itself out, because petrol is thinner than diesel and takes away the lubrication your fuel system depends on. Petrol is also made to resist igniting under compression — the reverse of what a diesel needs from its fuel — and that's where the clattering comes.
The shape of the problem is plain once you put those together. The damage is done by circulation, not by contact. Where that petrol is only in that tank, it is a fault of fuel, nothing more. The start of a mechanical one is a pump that has been working on that petrol — and whatever a worn pump sheds travels on with your fuel to the injectors beyond it.
Four situations we see around Maybush: how bad is petrol in a diesel?
Filled up, and not started: no case is better. On a forecourt, and really only there, that petrol is still limited to that tank — since everywhere else the car was driven to reach it. The job is emptying and cleaning on the spot.
Your ignition switched on, or a short start. Your system has been bled, and so petrol has left the tank and reached the filter and your lines. Normally nothing more than emptying, cleaning and sorting your filter, so still straightforward.
Those few miles driven were your pump working on fuel weakened by petrol throughout. How hard your car was driven matters as much as how far, and this work covers that tank, the lines, your filter and fresh fuel through the whole circuit. On the school run to Shirley Warren Primary & Nursery School, the mileage is short. Very different again: a trip to Southampton, under 3 miles away, or some miles on the Nursling Spur Motorway, under 3 miles from Maybush, where your engine never stopped running hard.
Driven till it protested. Rattling, a ragged idle, smoke, a throttle that has gone soft. The fuel isn't acting like diesel any more, and your engine is saying so. Pull up on the spot — on the verge on Rownhams Road, at the kerb, down a side road — and do not move it. The drain and flush-through still go first, and they deal with it: when a car is stopped early, long-term damage is very uncommon.
Maybush drivers and that petrol in a diesel myths they hear
Myth: topping up to full with diesel makes it fine. It doesn't. Nothing is removed by topping up — you are left with a fuller tank, still the same mixture. A diesel fuel system does not accept petrol by percentage in the way that guidance presumes.
"Newer diesels can handle a little petrol" — a myth, and nearer the opposite. A newer diesel runs its fuel through finer parts at higher pressure, which makes the protection count more, not less.
"It starts, it drives, so there is no harm" — the myth that catches most drivers than any other. Diesel in a petrol motor usually means a motor that won't run: the driver stops, and so does the damage. Whilst your pump grinds, a diesel fed petrol usually starts, ticks over and drives away as though nothing has happened. Being able to run isn't the same as being fine.
"A drop of two-stroke oil and drive it home" — a myth, borrowed from a fix from years ago, for a distinct issue. What petrol has thinned stays thinned, and that petrol stays inside the tank anyway.
If the motor has been run, part of the petrol sits in your filter and your lines, not the tank — and the next start pulls it straight back through the pump. So the myth "drain your tank yourself and you are sorted" does not hold. Also, a can of petrol drained by the roadside is genuinely dangerous.
Petrol in a diesel: how does it occur?
Nobody does it on purpose, and it's seldom carelessness. A diesel nozzle generally will not fit a petrol motor, yet the narrower petrol nozzle goes into the filler of a diesel almost without resistance — so forecourts make this one mistake easy, and just in one direction.
Routine and the car getting out of step is when it occurs. Courtesy car, hire car, or a car that is new. One petrol and one diesel on the drive of the same household. A familiar forecourt with the pumps in a different order. Racing for a train outside Redbridge and filling up en route. The first fill-up in a diesel Volkswagen Tiguan after years of driving petrol is exactly the moment it occurs. Throw in rain, a phone call or a back seat full of children, and your hand does what it has always done.
Next time you fill up around Maybush: avoiding petrol in a diesel
- Check the pump, not the colour. In the UK unleaded handles are normally green and diesel black, yet not on every forecourt. The label is what counts.
- The first fill in a new vehicle is the time to check your filler flap — inside it, or on the cap, plenty of cars state the fuel they take.
- Mark your key. In a home with one of each, a coloured fob or a sticker on your diesel's key does more than any amount of meaning to remember.
- It seems daft and it works: on your first fill in a new or hired car, say "diesel" aloud before you lift the nozzle off the petrol pump.
- Thinking about something else is when this becomes an easy mistake to make, so tuck your phone away then keep your mind on the petrol pump.
- A misfuel inhibitor helps, up to a point. Some diesels come with a filler built to reject a petrol nozzle, and add-on devices exist for vehicles without one. They are a backstop, not a reason to stop reading the pump.
- Noticing it mid-fill? Stop there and then. A weaker mixture results from less petrol in that tank, yet the next stage remains the same: don't fire it up.
Petrol already in a diesel in Maybush? Begin here
The order of things is short, then. Leave it unstarted, with your ignition off as well. Still on the forecourt, at Tesco or anywhere else? Ask the attendants to help you push it away from the pump. Then call 0333 366 0103 and tell us what was put in, about how much, and if it's run.
If it was AdBlue and not petrol, say so. That's a separate problem — corrosion and deposits rather than lost lubrication — and it has its own page for Maybush.
What makes one Maybush petrol in a diesel task cost more than the next
The four scenarios above are four different jobs, so no single quote for this would be fair. The scenario itself does most of the work of moving the cost. The ratio counts next, meaning how much of your tank is petrol, and then the location of your car and whether reaching it is safe for a technician.
That is why our engineers ask three queries before quoting instead of after: what was put in, how much, and whether it has run. Given those replies, you get a straight figure rather than a range.
About Maybush, for a moment
Maybush is a suburban area located on the coast in southern Hampshire, sitting approximately 27 metres above sea level. Maybush is situated near the city of Southampton, with Coxford, Wimpson, and Shirley Warren as nearby places. Maybush has a population of around 10343 people and is characterised by semi-detached housing. Maybush is also within commuting distance to London, being around 69.6 miles away.
Fuel drain cover across Hampshire, Maybush included
The vans answering petrol in diesel calls in Maybush, in the SO postcode area, also work the locations near it, Coxford, Wimpson and Shirley Warren included. A forecourt, a supermarket car park, a lay-by or your own driveway are all places our engineers drain, and your vehicle does not need to move to us.
Still at the petrol pump in Maybush?
Then, you couldn't be in a better place. Keep it off. Call.