Petrol in a Diesel Car in Weston Favell: How Worried Should You Be?
Less than you probably are, provided it hasn't been started. "Have I ruined it?" is the first thing everyone in Weston Favell asks, and the honest answer is normally no, because petrol left in a diesel tank hurts nothing till it is drawn through your fuel system — by ignition priming, by your starter, or by driving. Leave the engine off and call Petrol in Diesel — that keeps it like that. The remainder of this page sets out 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.
Petrol in a diesel: what does it do to the motor?
On its way through a motor, diesel has two tasks. Before it ignites, it protects — then it ignites. Made to extremely fine clearances, the injectors and the pump depend on the diesel moving through them to stop their surfaces wearing against one another.
Poorly 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 strips out the lubrication the fuel system relies on. Petrol is also designed to resist igniting under compression — the reverse of what a diesel wants from its fuel — and that's where any rattling comes.
Seen together, they show what shape the trouble has. Contact doesn't do the harm — circulation does. Where that petrol is only inside that tank, it's a fault of fuel, nothing more. The start of a mechanical one is a pump that has been labouring on that petrol — and whatever a worn pump sheds moves on with your fuel to your injectors beyond it.
Four scenarios our technicians see in Weston Favell: how bad is petrol in a diesel?
Fuelled up, never started. The best case there is. The petrol is inside that tank and just that tank, and the job is a drain and a flush where your car sits. This is the one situation that can only really take place on a forecourt, as anywhere else your car has been driven to get there.
Started for a moment, or only your ignition on. Once primed, your system has drawn petrol out of that tank as far as the fuel filter and your lines. Normally nothing more than emptying, rinsing and sorting the fuel filter, and so still easy.
Your pump has spent a few miles on weakened fuel — that's what driving the vehicle meant. Miles is only half of that; how hard it was driven matters just as much. Either way the work runs to that tank, your lines, your filter and clean fuel through the whole circuit. Short trips, like the school run to Weston Favell CofE Primary School, are one thing. Very different once more: a trip to Milton Keynes, under 15 miles away, or some miles on the M1, under 5 miles from Weston Favell, where the engine never stopped working hard.
Clattering, an uneven idle, smoke, a throttle gone soft: driven till it complained. That is the engine telling you its fuel no longer is acting like diesel. Leave it wherever it has stopped: a lay-by, a side street, the verge on Church Way Court. A car stopped early very seldom has long-term damage, since the drain and the flush-through, which still go first, sort it out.
Myths Weston Favell people hear about petrol in a diesel
Myth: topping up to full with diesel makes it fine. It doesn't. Nothing comes out when you top up — your tank just holds more of the same mixture. Percentage isn't how a diesel fuel system tolerates petrol, however much that advice assumes.
Myth: a newer diesel copes with a bit of petrol. If anything, the reverse. At higher pressure, through smaller parts: that is how a current diesel handles its fuel, so the lubrication counts for more, not less.
One myth that catches motorists off guard: if it starts and drives, it must be unharmed. A petrol motor fed diesel normally won't run, so the driver stops and the harm stops with them. A diesel fed petrol generally starts, ticks over and drives away as if nothing has happened, whilst your pump grinds. A running engine does not mean fine.
Not so: a two-stroke additive makes it safe to drive home. It was an old fix, supposed for another fault. None of what petrol weakened gets put back by it — and later, that tank still contains that petrol.
The next start sends petrol back round your pump out of the lines and the fuel filter, where some of it ends up once the engine has run. That's why draining your tank yourself does not sort it — a myth. It's also really risky to drain petrol into a can by the kerbside.
Petrol in a diesel: how does it occur?
No one does it on purpose, and it is rarely carelessness. One way only, since of the nozzles: the narrower petrol one slides inside a diesel filler with almost no resistance, whereas the diesel one mostly will not fit a petrol vehicle. That's how the forecourt makes it simple.
When habit and the car stop matching, it takes place. A new car, 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. Rushing for a train outside Northampton and filling up en route. The first fill-up in a diesel Volkswagen Golf after years of driving petrol is exactly the moment it happens. Throw in a back seat full of children, a phone call or rain, and habit wins.
How to avoid petrol in a diesel at your next fill-up around Weston Favell
- A green handle for unleaded and black for diesel is normal in the UK — but not on each forecourt. Trust the label on the petrol pump, not the colour.
- The first fill in a new car is the time to check your filler flap — inside it, or on the cap, plenty of motors state which fuel they take.
- A coloured fob or a sticker on your diesel's key achieves more than any amount of meaning to remember, in a home with one of each.
- Say it before you lift it. On your first fill in a new or hired car, say "diesel" aloud before you take the nozzle off the petrol pump. It sounds daft and it does the trick.
- Whilst you are thinking about something else, this is an easy mistake to make — so put the phone away.
- A misfuel inhibitor helps, up to a point. Some diesels have a filler designed to refuse a petrol nozzle, and add-on devices exist for cars without one. They are a safety net, not a reason to stop reading the pump.
- Stop the moment you notice. Less petrol inside the tank makes a weaker mixture. It does not change what to do next, which is still not to start it.
Petrol already in a diesel around Weston Favell? Begin here
The order of things is brief, then. Do not start the vehicle, and do not switch your ignition on. The staff at the forecourt — whether at Tesco itself or wherever you filled up — will usually help roll it away from the pump if you ask. What went in, about how much, and if it has run: tell us those when you ring 0333 366 0103.
Say so if it was AdBlue instead of petrol: it's a different issue, with its own page for Weston Favell, because AdBlue brings corrosion and deposits instead of lost lubrication.
What makes one Weston Favell petrol in a diesel job cost more than the next
Four separate tasks lie behind the four situations above — which is why there is no fair single price. The scenario itself does most of the work of moving your cost. Two things follow that: the petrol that got in as a proportion of what your tank takes, then the place your car is in and whether a van can get to it safely.
That's why our engineers ask three questions before quoting instead of after: what went in, how much, and whether it has run. Those answers change a range into a straight figure.
About Weston Favell
Weston Favell is a suburban area in Northamptonshire, situated approximately 88 metres above sea level in the East Midlands region. Weston Favell lies near several neighbouring communities, including Abington Vale and Standens Barn, and is within commuting distance of major cities like Milton Keynes. Weston Favell has a population of around 3871 residents, predominantly living in detached housing. Weston Favell is also relatively close to London, at a distance of about 59.7 miles.
Fuel drain cover across Northamptonshire, Weston Favell included
Weston Favell rests in the NN postcode area, and our vans that answer petrol in diesel jobs there work the locations around it as well — Abington Vale, Abington and Standens Barn among them. We drain where the car is — your own driveway, a lay-by, a supermarket car park, a forecourt — so it does not have to come to us.
Still at the petrol pump around Weston Favell?
The best spot there is, then — that is where you are. Keep it turned off, and ring.