Woodside: Petrol in a Diesel Car? How Worried to Be
Probably less than you are now — provided nobody has started it. Until the ignition primes the pump, the starter cranks, or your vehicle is driven, petrol in a diesel tank just sits there and does nothing. Which makes the truthful reply to the first Woodside query — "have I ruined it?" — usually no. To keep the car that way, ring Petrol in Diesel and leave the motor switched off. Read on for three things: the effect petrol has inside a diesel engine, the clues of how far it has got, and ways to make sure you don't do it again.
Inside the motor: what petrol in a diesel really does
Passing through an engine, diesel does two jobs at once. Lubricating comes before burning; it does both. Made to very fine gaps, the fuel injectors and your pump depend on the diesel moving through them to stop their surfaces wearing against one another.
Of those two tasks, petrol manages the first badly and the second not at all. Being less viscous than diesel, petrol strips away the protection a fuel system needs, leaving a pump running on the mixture wearing itself. It's equally made to resist igniting under compression — the reverse of what a diesel needs — which is why you hear the rattling.
Combined, those leave the shape of the problem plain. The damage is done by movement, not by contact. Where that petrol is only inside the tank, it is an issue of fuel, nothing more. Whatever a worn pump sheds travels on, borne by the fuel, into the injectors further along, which is why a pump that has worked on that petrol is where a mechanical problem starts.
Petrol in a diesel in Woodside: how bad is it? Four situations
Filled up, and never started: no case is better. On a forecourt, and truly only there, that petrol is still limited to your tank — because anywhere else your car was driven to reach it. The task is draining and purging on the spot.
Started for a second, or just the ignition on. The system has been primed, so petrol has left that tank and reached the fuel filter and the lines. That is generally still a simple task — a drain, a flush, and the fuel filter dealt with.
Those few miles driven were the pump working on fuel thinned by petrol the whole way. Tank, lines, filter, then fresh fuel run through the whole system: that is the work, and the way your car was driven counts as much as the miles. On the school run to The Hills Academy, the mileage is short. Getting as far as Milton Keynes, under 25 miles away, makes a very different task — as does any miles on the M1, under 15 miles from Woodside, with the motor labouring hard the whole time.
Driven till it protested. Rattling, a ragged idle, smoke, a throttle that has gone soft. That is your engine telling you its fuel no longer is behaving like diesel. Pull up where you are — on the verge on Putnoe Street, at the kerb, down a side road — and don't move it again. What goes first is still the fuel drain and flush, and that takes care of it, with permanent damage very unusual when a car is stopped soon.
Woodside drivers and that petrol in a diesel stories they hear
Myth: "Fill it the rest of the way with diesel and it'll be fine." It will not. Topping up takes out nothing; it gives you a fuller tank of the same mix. Percentage isn't how a diesel fuel system tolerates petrol, whatever that guidance supposes.
Myth: "A newer diesel can cope with a bit of petrol." If anything, the reverse. At higher pressure, through finer parts: that's how a current diesel handles its fuel, and so the protection counts more, not less.
The myth that catches drivers off guard: if it starts and drives, it must be unharmed. Feed diesel to a petrol motor and it normally won't run, and so the motorist stops — and the harm stops with them. A diesel fed petrol usually starts, ticks over and drives away as though nothing has happened, whilst your pump wears. A running engine does not mean fine.
An outdated fix for a different issue is behind this one. Myth: "Add some two-stroke oil and drive the car home." It doesn't put back what petrol has weakened, and the petrol is still inside that tank after that.
If the engine has run, part of the petrol sits in the filter and the lines, not the tank — and the next start sends it right back through your pump. So the myth "drain that tank yourself and you are sorted" doesn't hold. Besides, petrol drained into a can by the road is truly risky.
How it happens: petrol in a diesel
No one does it on purpose, and it's rarely carelessness. A diesel nozzle mostly won't fit a petrol motor, but the slimmer petrol nozzle goes into the filler of a diesel nearly without resistance — so forecourts make this one error straightforward, and only in that direction.
Routine and your car falling out of step is when it happens. Hire cars, courtesy cars, and vehicles that are new to you. Two motors on one driveway, one petrol, one diesel. Your ordinary forecourt, its pumps now in a different order. A hurried fill on the way to Bedford St Johns with a train to catch. Years of petrol vehicles behind you, a diesel Skoda Octavia in front of you on the forecourt for its first tank — that's when. Add rain, a phone call or a back seat full of children, and your hand does what it has always done.
Woodside drivers: how to avoid petrol in a diesel next time
- A green handle for unleaded and black for diesel is normal in the UK — yet not on each forecourt. Trust the label on the petrol pump, not the colour.
- Inspect your filler flap. Plenty of cars state the fuel inside the flap or on the cap. Look at it on the first fill in a car you don't know.
- Label the key. In a house with one of each, a coloured fob or a sticker on the diesel's key does more than any amount of intending to remember.
- Say it before you lift it. On the first fill in a new or hired car, say "diesel" out loud before you lift the nozzle off the petrol pump. It sounds daft and it works.
- Mistakes like this are simple to make whilst your mind is on something else, so the phone goes away.
- 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.
- Stop as soon as you notice. Less petrol in that tank makes a thinner mix. It doesn't change what to do next, which is still not to fire it up.
Petrol already in a diesel in Woodside? Begin here
Then the order of things is short. Never crank it, and do not switch the ignition on. The staff on the forecourt — whether at JET itself or wherever you filled up — will normally help roll it away from the pump if you ask. Call 0333 366 0103 next, with three facts — the fuel, the approximate amount, and if it has run.
AdBlue, not petrol? Then tell us. Corrosion and deposits, not lost lubrication, make it a separate issue — Woodside has a page just for it.
Woodside petrol in a diesel jobs: why one costs more than another
An honest single price does not exist here: four situations, four separate tasks. What shifts the cost is mostly which of them you are in. The ratio counts next, meaning how much of that tank is petrol, and then the location of your car and whether getting to it is safe for a technician.
What got in, how much, and if it's run — three questions we ask before quoting, not after, for precisely that reason. The answers turn a range into a straight figure.
About Woodside
Woodside is a suburban area in Bedfordshire, situated inland at an elevation of 39 metres, with semi-detached housing being the predominant type of accommodation. Woodside lies approximately 46.6 miles north of London and 15.4 miles southeast of Milton Keynes, near the neighbouring areas of Putnoe, Goldington, and Brickhill. Woodside has a population of around 6367 residents, making it a moderately sized community in the region.
Fuel drain cover in Woodside and across Bedfordshire
Woodside rests in the MK postcode area, and our vans that answer petrol in diesel calls there work the spots near it as well — Putnoe, Goldington and Brickhill among them. No need to move your vehicle to us. Forecourts, supermarket car parks, lay-bys and your own driveway are all spots we drain.
In Woodside and still at the pump?
The best place there is, then — that is where you are. Call, and leave it turned off.