Petrol in a Diesel Car in Dreghorn: How Worried Should You Be?
Not started? Then less worried than you probably feel. Until the ignition primes the pump, the starter turns, or your vehicle is driven, petrol in a diesel tank simply waits there and does no harm. Which means the truthful reply to that first Dreghorn query — "have I ruined it?" — normally no. Petrol in Diesel is who to call, with your motor left off, so it remains that way. Below, this page sets out what petrol really does inside a diesel, how far it might have gone, and how to stop it happening to you again.
The engine and petrol in a diesel: what goes on
Diesel does two jobs on its way through an engine. It protects to begin with, and after that does it burn. Made to very fine tolerances, the fuel injectors and the pump depend on the diesel flowing through them to keep their surfaces from wearing against one another.
The second task petrol doesn't do at all, and the first it does poorly. A pump running on a petrol mix is wearing itself out, since petrol is thinner than diesel and strips out the protection your fuel system relies 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 rattling comes.
Taken together, they make clear the shape the problem takes. Contact doesn't do the damage — circulation does. All a tank with petrol in it amounts to is a fuel problem. After your pump has been running on that petrol, a mechanical fault has started: anything shed by a pump that is wearing down travels onward to the injectors with the fuel.
Petrol in a diesel around Dreghorn: how bad is it? Four cases
Fuelled, and never started: no case is better. Just the tank has petrol in it, and so the task is draining your tank and purging your system where the car sits. This situation can only truly take place at a forecourt: anywhere else, the vehicle got there by being driven.
Ignition on, or started for a second. Once primed, the fuel system has pulled petrol from your tank as far as the fuel filter and the lines. That is generally still a straightforward job — a drain, a flush, and the filter dealt with.
Those few miles driven meant the pump running on fuel thinned by petrol the whole way. How hard your car was driven counts as much as how far, and the work takes in that tank, the fuel lines, your filter and fresh fuel through the entire system. Short trips, like the school run to the local primary school, are one matter. Any mileage on the M8, under 5 miles from Dreghorn, means the engine has worked hard throughout, and a run to Edinburgh, under 5 miles away, is a very different task too.
Driven until it complained. Rattling, an uneven idle, smoke, a throttle that has gone soft. What you are hearing is the motor signalling fuel that no longer acts like diesel. Whether it is the verge on The Gallolee, a lay-by or a side street, stop where you are and leave it. Long-term damage is very uncommon when a vehicle is pulled over quickly, and the fuel drain and flush-through that still come first deal with it.
Myths Dreghorn motorists hear about petrol in a diesel
It will not be fine. The myth: "Fill it the rest of the way with diesel and it'll be." Nothing is removed by topping up — you are left with a bigger tank, still the same mix. Percentage is not how a diesel fuel system copes with petrol, however much that guidance assumes.
If anything, the reverse is true. Myth: "A newer diesel can cope with a bit of petrol." At higher pressure, through smaller parts: that's how a newer diesel moves its fuel, so the lubrication counts more, not less.
This is the one that catches people. Myth: "If it starts and drives, there is no harm done." The motorist of a petrol engine fed diesel normally has no choice but to stop, because it will not run, and the harm stops with them. A diesel fed petrol usually starts, ticks over and drives away as if nothing has happened, whilst the pump wears. Being able to run isn't the same as being fine.
"A drop of two-stroke oil and drive it home" — a myth, taken from a fix from years ago, for a separate problem. None of what petrol thinned gets put back by it — and later, the tank still contains that petrol.
Myth: "Drain your tank yourself and you are sorted." After the motor has been run, some of that petrol is no longer in your tank: it is in the fuel filter and your lines, and it goes straight back through your pump on your next start. It's also truly hazardous to drain petrol into a can at the roadside.
Petrol in a diesel: how does it occur?
It is rarely carelessness, and nobody does it on purpose. A diesel nozzle generally will not go into a petrol motor, but the slimmer petrol nozzle goes into the filler of a diesel almost without resistance — so forecourts make this one mistake straightforward, and only in that direction.
The moment habit stops matching your car is the moment it happens. Hire cars, courtesy cars, and cars that are new to you. Households running one of each, petrol and diesel. Your ordinary forecourt, its pumps now in a different order. Fuelling up in a rush en route to Kingsknowe, with a train to catch. Years of petrol vehicles behind you, a diesel Volkswagen Tiguan in front of you at the forecourt for its first tank — that's when. Your hand repeats what it has always done once you add rain, a phone call or a back seat full of kids.
Dreghorn people: how to prevent 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.
- In a vehicle you don't know, look inside the flap over the filler or at the cap before your first fill: plenty of motors state the fuel there.
- Good intentions do less than a sticker or a fob in a bright colour on the diesel's key when a household has one of each. So label it.
- "Diesel", aloud, before you pick up the nozzle — every time a new or hired car needs its first tank. It sounds daft. It does the trick.
- Mistakes like this are straightforward to make whilst your mind is on something else, so your phone goes away.
- 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 safety net, not a reason to stop checking the pump.
- Spotting it halfway? Stop at once. A thinner mixture results from less petrol in your tank, yet the next step stays the same: don't crank it.
Put petrol in a diesel in Dreghorn already?
The order of things is brief, then. Don't start it, and do not turn your ignition on. If you are still on the forecourt — Tesco or anywhere else — ask the staff to help you push the car clear of the pump. What got in, about how much, and if it has run: tell us those when you ring 0333 366 0103.
Say so if it was AdBlue rather than petrol: it is a different fault, with its own page for Dreghorn, since AdBlue brings corrosion and deposits instead of lost lubrication.
What makes one Dreghorn petrol in a diesel job cost more than the next
There's no fair single quote for this, because the four situations above are four separate jobs. Mostly, your cost moves with which one you are in. Where the car is matters too, and whether our van can safely get to it, after the ratio of petrol to what the tank takes.
That's why we ask three queries before costing instead of after: what was put in, how much, and whether it's run. Given those replies, there is a straight figure instead of a range.
About Dreghorn, for a moment
Dreghorn is a suburban area located on the outskirts of Edinburgh, sitting near the River Almond in the City of Edinburgh. Dreghorn is characterized by its predominantly flat-type housing and is situated close to nearby places such as Oxgangs and Colinton. Dreghorn has a population of around 4201 residents and is approximately 138 metres above sea level. Dreghorn is also relatively close to the city centre, being only 3.9 miles away from Edinburgh.
Fuel drain cover across City of Edinburgh, Dreghorn included
Oxgangs, Colinton Mains and Colinton are among the locations around Dreghorn that the same teams work, answering petrol in diesel jobs across Dreghorn's EH postcode area. No need to move the car to us. Forecourts, supermarket car parks, lay-bys and your own driveway are all spots where we work.
In Dreghorn and still at the pump?
Then you are in the best position there is. Keep the car turned off, then ring.