Should You Worry? Petrol in a Diesel Car in Dickleburgh
If it has not been started, you can worry less than you likely are. Till the ignition primes the pump, the starter turns, or the car is driven, petrol in a diesel tank simply sits there and does nothing. Which makes the truthful reply to that first Dickleburgh query — "have I ruined it?" — normally no. Petrol in Diesel is who to phone, with your motor left off, and so it remains that way. Below, this page sets out what petrol actually does inside a diesel, how far it may have gone, and how to stop it happening to you again.
Inside the engine: what petrol in a diesel really does
Diesel does two jobs on its way through an engine. Before it ignites, it protects — and then it combusts. What keeps the surfaces inside the high-pressure fuel pump and the injectors from wearing down against each other is your diesel passing through them — they're built to very fine tolerances.
Petrol handles the first task badly and the second not at all. Being less viscous than diesel, petrol strips away the lubrication a fuel system needs, so a pump running on that mixture to wear itself. It is equally made to resist igniting under compression — the opposite of what a diesel needs — which is where you hear the knocking.
Combined, those leave the shape of the trouble clear. Contact doesn't do the harm — circulation does. All a tank with petrol in it amounts to is a fuel fault. Whatever a worn pump sheds travels on, carried by the fuel, into your injectors downstream, which is why a pump that has worked on that petrol is where a mechanical issue begins.
Petrol in a diesel in Dickleburgh: how serious is it? Four cases
The best case there is: filled up, never started. Being at a forecourt is what makes this the case: elsewhere, the vehicle has been driven there to begin with. With the petrol held in that tank alone, it's emptied and purged right where it stands, and nothing more is needed.
Started for a second, or only your ignition on. Petrol has left that tank and reached your filter and the lines, since your system has been primed. That is usually still an easy task — a drain, a flush, and your filter seen to.
Driven a couple of miles. Now the pump has spent those miles labouring on weakened fuel. The work is that tank, your lines, the filter and fresh fuel through the whole system, and how hard the vehicle was driven matters as much as how far. Driving the children to Dickleburgh Church of England Primary Academy (With Pre-School) is one kind of trip. Getting as far as Norwich, under 25 miles away, makes a very different job — as does any mileage on the M11, under 50 miles from Dickleburgh, with the engine working hard all the way.
Knocking, a ragged idle, smoke, a throttle gone soft: driven till it complained. What you are hearing is the motor reporting fuel that no longer behaves like diesel. Pull up wherever you are — the verge on Rectory Road, a lay-by, a side street — then leave the vehicle where it is. A car pulled over early very seldom has lasting damage, since the fuel drain and the flush-through, which still go first, deal with it.
Petrol in a diesel stories Dickleburgh drivers hear
Myth: "Fill it the rest of the way with diesel and it will be fine." It will not. A bigger tank of the same mixture is all it gives, because topping up removes nothing. That advice assumes a diesel fuel system tolerates petrol by percentage. It doesn't.
"Current diesels can handle a little petrol" — a myth, and nearer the opposite. At higher pressure, through smaller components: that's how a newer diesel moves its fuel, and so the protection matters for more, not less.
One myth that catches drivers out: if it starts and drives, it must be unharmed. Diesel in a petrol motor usually leaves a motor that will not run: the driver stops, and so does the harm. While your pump grinds, a diesel fed petrol normally starts, ticks over and drives away as if nothing has happened. Running does not mean fine.
Not so: a two-stroke additive makes it safe to drive home. It is an old fix, meant for another issue. What petrol has diluted stays weakened, and that petrol stays inside that tank anyway.
"Drain it yourself and you are sorted" — a myth, because after it has been running some petrol lies in your filter and lines, waiting to go right back through your pump on your next start. It's also truly risky to drain petrol into a can at the kerbside.
How petrol ends up: petrol in a diesel
Carelessness is seldom the cause, and no one means to do it. A diesel nozzle mostly won't fit a petrol car, yet the smaller petrol nozzle goes into the filler of a diesel nearly without resistance — so forecourts make this one error straightforward, and just in one direction.
When routine and the vehicle stop matching, it takes place. A new motor, a hire car or a courtesy car. Households running one of each, petrol and diesel. The pumps in a different order on a well-known forecourt. A train to catch, and a rushed fill en route to Diss. Precisely the moment it occurs: after years of driving petrol, a driver fills a diesel Volkswagen Golf for the first time. Throw in rain, a phone call or a back seat full of kids, and the hand repeats what it has always done.
Next time you fill up around Dickleburgh: avoiding petrol in a diesel
- Not every forecourt in the UK keeps to green for unleaded and black for diesel, even if most usually do. Check the pump's label; the colour is just a hint.
- Inspect the filler flap. Many motors state the fuel type inside the flap or on the cap. Look at it on your first fill in a car you don't know.
- Good intentions do less than a sticker or a fob in a bright colour on your diesel's key when a house has one of each. So label it.
- It sounds silly and it works: on your first fill in a new or hired car, say "diesel" aloud before you take the nozzle off the petrol pump.
- Thinking about something else is when this becomes an easy mistake to make, and so put the phone away and keep your mind on the petrol pump.
- Some diesels come with a filler designed to block a petrol nozzle, and devices you can add exist for vehicles without one. Such an inhibitor helps up to a point — as a backstop, not a reason to stop checking the petrol pump.
- Spotting it halfway? Stop at once. A thinner blend follows from less petrol inside the tank, but the next stage remains the same: don't start the car.
Dickleburgh: already put petrol in a diesel?
Then the order of things is brief. Don't turn the ignition on, and don't fire it up. Ask the staff to help you push it clear of the pump if you're still at the forecourt, whether that is BP or somewhere else. Next, 0333 366 0103. We will ask what got in, roughly how much, and if it has been run.
AdBlue, not petrol? Then say so. Corrosion and deposits, not lost lubrication, make it a separate fault — Dickleburgh has a page all for it.
What makes one Dickleburgh petrol in a diesel job cost more than the next
The four scenarios above are four different tasks, so no single price for this would be honest. Which of them you are in is mostly what shifts your cost. Where the vehicle is counts too, and whether a van can safely reach it, after the ratio of petrol to what that tank holds.
What got in, how much, and whether it's run — three queries we ask before quoting, not after, for exactly that reason. Given the replies, there is a straight figure rather than a range.
About Dickleburgh itself
Dickleburgh is a small village in south Norfolk, situated inland at an elevation of around 37 metres. Dickleburgh lies near the villages of Thelveton and Shimpling, and is close to Dickleburgh Moor. Dickleburgh has a population of approximately 610 people, and its housing stock is predominantly made up of detached homes. Dickleburgh is located about 16.6 miles from Norwich and 83.1 miles from London.
Fuel drain cover across Norfolk, Dickleburgh included
Dickleburgh waits in the IP postcode area, and our teams that answer petrol in diesel call-outs there work the places near it as well — Dickleburgh Moor, Thelveton and Shimpling among them. You need not bring your car to us. Forecourts, supermarket car parks, lay-bys and your own driveway are all places where we work.
Still at the petrol pump in Dickleburgh?
Then you are in the best spot there is. Leave the vehicle turned off, and ring.