Bramley Green: Petrol in a Diesel Car? How Worried to Be
Probably less than you already are — provided nobody has started the vehicle. Petrol sitting in a diesel tank does nothing to your engine until something pulls it through your fuel system — your ignition priming the pump, your starter, or the drive itself. So the fair answer to the first question anyone around Bramley Green asks, "have I wrecked it?", is generally no. To keep it like that, ring Petrol in Diesel and leave the engine switched off. Read on for three things: the effect petrol has inside a diesel engine, the clues of how far it has got, and the way to make sure you don't repeat it.
Petrol in a diesel: what does it do to the engine?
On its way through an engine, diesel does two jobs. It burns, and before it ignites it lubricates. Built to extremely fine gaps, your injectors and your pump depend on the diesel moving through them to stop their surfaces wearing against one another.
Petrol handles the first job poorly and the second not at all. Being less viscous than diesel, petrol strips out the protection a fuel system needs, leaving a pump on that mixture to wear itself. It is equally made to resist igniting under compression — the reverse of what a diesel needs — which is where you get the knocking.
The shape of the trouble is clear when you put those together. Contact does not do the damage — circulation does. Petrol in a tank is a fuel fault. Whatever a worn pump sheds goes on, carried by the fuel, into the injectors further along, which is why a pump that has worked on the petrol is where a mechanical problem begins.
How serious is petrol in a diesel? Four situations our engineers see in Bramley Green
The best case there can be: filled up, not once started. Being at a forecourt is what makes this possible: elsewhere, the car has been driven there to begin with. With that petrol kept inside your tank alone, it's drained and rinsed right where it stands, and nothing more is needed.
Started for a second, or just the ignition on. Petrol has left that tank and reached your filter and your lines, since your system has been bled. Normally nothing more than emptying, purging and seeing to the filter, and so still straightforward.
The pump has worked a couple of miles on diluted fuel — that's what driving the car does. Tank, lines, filter, then fresh fuel run through the whole circuit: that's this work, and the way the vehicle was driven counts as much as the miles. Short trips, such as the school run to Bramley Church of England Primary School, are one matter. Any distance on the M3, under 5 miles from Bramley Green, means the motor has worked hard throughout, and a run to Winchester, under 25 miles away, is a very different job as well.
Driven on until it protested — knocking, smoke, a lumpy idle, a soft throttle. The fuel isn't acting like diesel any more, and the motor is telling you. Whether it's the verge on Sherfield Road, a lay-by or a side road, stop there and leave it. What goes first is still the fuel drain and flush-through, and that sorts it out, with permanent damage very unusual if a vehicle is pulled over soon.
Bramley Green drivers and that petrol in a diesel myths they hear
False: topping up to full with diesel makes it fine. It does not. A bigger tank of the same mix is all it gives, because topping up removes nothing. The assumption behind the guidance — that diesel fuel systems accept petrol by percentage — is wrong.
"Current diesels can handle a little petrol" — a myth, and closer to the opposite. Lubrication counts more on newer diesels, not less, since their fuel runs through more precise components at higher pressure.
One myth that catches people out: if it starts and drives, it must be unharmed. Diesel in a petrol motor normally leaves a motor that won't run: the motorist stops, and so does the harm. Nothing seems to have happened when a diesel fed petrol fires up, ticks over and drives away, as it usually will; meanwhile the pump wears. Fine and running aren't the same at all.
Myth: "Add some two-stroke oil and drive the car home." It is an old fix for a different problem. The petrol is still in your tank after that, and what it has weakened is not put back.
"Drain it yourself and you're sorted" — a myth, because after it's been running some petrol lies in the fuel filter and lines, ready to go right back through your pump at your next start. It is also truly dangerous to drain petrol into a can by the kerbside.
How does petrol in a diesel happen?
Carelessness is rarely the cause, and nobody means to do it. A diesel nozzle generally will not fit a petrol motor, but the slimmer petrol nozzle goes into the filler of a diesel almost without resistance — so forecourts make this one mistake easy, and only in one direction.
The moment habit stops matching the car is the moment it occurs. Hire cars, courtesy cars, and vehicles that are new to you. A household with one petrol and one diesel on the driveway. A familiar forecourt with the pumps in a different order. Fuelling up in a hurry on the way to Bramley (Hants), with a train to catch. Years of petrol vehicles behind you, a diesel Renault Megane in front of you at the forecourt for its first tank — that's when. With rain, a call arriving, or children to deal with, the hand simply does what it has always done.
Bramley Green motorists: how to avoid petrol in a diesel next time
- A green handle for unleaded and black for diesel is usual in the UK — but not on each forecourt. Go by the label on the petrol pump, not the colour.
- Plenty of cars state the fuel inside your filler flap or on the cap, and so check it on the first fill in any motor you do not know.
- Good intentions do less than a sticker or a fob in a vivid colour on your diesel's key if a house has one of each. So mark it.
- "Diesel", aloud, before you pick up the nozzle — every time a new or hired car gets its first tank. It sounds daft. It does the trick.
- Tuck your phone away. This is an easy mistake to make whilst you're thinking about something else.
- A misfuel inhibitor helps, up to a point. Some diesels come with a filler designed to reject a petrol nozzle, and add-on devices are available for motors without one. They are a backstop, not a reason to stop checking the pump.
- Less petrol means a thinner blend, and so stop the moment you notice — though remembering that the next stage is unchanged. It's still not to crank it.
Put petrol in a diesel around Bramley Green already?
Short and simple, then, is the order of things. Leave it unstarted, with your ignition switched off too. Ask the staff to help you push it away from the pump if you're still on the forecourt, whether that's BP or anywhere else. Ring 0333 366 0103 next, with three answers — your fuel, the approximate volume, and if it's run.
AdBlue, not petrol? Then tell us. Corrosion and deposits, not lost protection, make it a different problem — Bramley Green has a page just for it.
One petrol in a diesel task around Bramley Green costs more than another. Why?
Four separate tasks sit behind the four situations above — which is why there's no honest single quote. Which of them you're in is chiefly what moves your cost. Where the car is matters too, and whether a technician can safely get to it, after the ratio of petrol to what your tank takes.
What got in, how much, and if it has run — three questions our engineers ask before quoting, not after, for precisely that reason. A range becomes a straight figure once the answers are in.
About Bramley Green itself
Bramley Green is a village situated in a riverside setting in Hampshire, with an elevation of around 59 metres. Bramley Green lies near the larger village of Bramley and other nearby places such as Sherfield on Loddon and Fair Oak Green. Bramley Green has a population of approximately 1645 residents and predominantly features detached housing. Bramley Green is located near the city of Winchester, which is about 21.5 miles away, and is also within commuting distance to London, at around 41.6 miles away.
Fuel drain cover in Bramley Green and across Hampshire
Petrol in diesel jobs in Bramley Green — part of the RG postcode area — go to teams that likewise cover the locations round it, Bramley, Sherfield on Loddon and Fair Oak Green included. A forecourt, a supermarket car park, a lay-by or your own driveway are all spots our technicians work, and your car does not need to move to us.
Still at the petrol pump around Bramley Green?
Then you're in the best position there can be. Switched off it remains; then call.