Should You Worry? Petrol in a Diesel Car in Naunton Park
Unstarted? Then less anxious than you likely are. Everyone around Naunton Park starts with "have I ruined it?", and the honest answer is normally no: petrol resting in the tank of any diesel stays harmless till priming, cranking or driving pulls it into your fuel system. Leave the motor off and ring Petrol in Diesel — that is how you keep it like that. What petrol really does to a diesel, how to judge how far it has gone, and how to stop it from happening again: that's the remainder of this page.
The motor and petrol in a diesel: what happens
On its way through an engine, diesel has two tasks. It combusts, and before it burns it lubricates. The high-pressure fuel pump and the injectors are designed to extremely fine clearances, and the diesel passing through them is what keeps those surfaces from grinding against one another.
Petrol handles the first job badly and the second not at all. A pump running on a petrol mix is wearing itself out, because petrol is runnier than diesel and strips out the protection 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 is where any knocking starts.
The shape of the problem is clear when you put those together. It is movement that does the damage, not contact. A tank with petrol in it is a fuel issue. Whatever a worn pump sheds goes on, carried by your fuel, into the injectors further along, which is why a pump that has worked on the petrol is where a mechanical issue starts.
Naunton Park, petrol in a diesel: four situations, from mild to major
Fuelled up, not once started. The best case there can be. That petrol is in the tank and only that tank, and the task is a drain and a flush where your car sits. This is the one situation that can only truly take place on a forecourt, since anywhere else the vehicle has been driven to get there.
Ignition on, or started for a moment. Once primed, your system has drawn petrol out of the tank up to the fuel filter and the lines. That's usually still an easy job — a drain, a flush, and your filter dealt with.
Driven a few miles. Now the pump has spent those miles labouring on weakened fuel. Mileage is only half of that; how hard it was driven matters equally. Either way the work includes your tank, the lines, the filter and clean fuel through the whole system. The school run to Naunton Park Primary School is one thing. A run as far as Gloucester, under 10 miles away, is a very different job. So is any distance on the M5, under 5 miles from Naunton Park, where your engine has been running hard the whole time.
Driven on till it complained — rattling, smoke, a lumpy idle, a soft throttle. That is your motor telling you its fuel no longer is acting like diesel. Whether it's the verge on Old Bath Road, a lay-by or a side street, stop there and leave it. Permanent damage is very uncommon when a car is stopped early, and the drain and flush-through that still come first sort it out.
Naunton Park motorists and that petrol in a diesel myths they hear
False: topping up to full with diesel makes it fine. It doesn't. Topping up removes nothing; it gives you a fuller tank of the same mixture. Percentage is not how a diesel fuel system tolerates petrol, however much that advice presumes.
Myth: "A newer diesel can cope with a bit of petrol." If anything, the opposite. A current diesel sends its fuel through more precise parts at higher pressure, which makes the protection count more, not less.
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 does; meanwhile your pump wears. Fine and running aren't the same at all.
Myth: a two-stroke additive makes it safe to drive home. It was an old workaround, meant for another problem. It doesn't put back what petrol has weakened, and that petrol is still in that tank afterwards.
"Drain it yourself and you are sorted" — a myth, because after it's been running some petrol lies in the fuel filter and lines, ready to go straight back through the pump at the next start. Clearing petrol into a can by the roadside is also really risky.
How does petrol in a diesel occur?
On purpose? Never. Through carelessness? Rarely, if ever. The petrol nozzle is the smaller of the two and slips into a diesel filler with almost no resistance; a diesel nozzle generally will not go into a petrol vehicle at all. The forecourt makes it easy, and the slip runs one way.
When routine and your car stop matching, it happens. Any vehicle that is new to you — hired, on loan as a courtesy car, or just bought. Households running one of each, petrol and diesel. A forecourt you know, but with its pumps arranged differently. Fuelling up in a rush en route to Cheltenham Spa, with a train to catch. Precisely the moment it happens: after years of driving petrol, someone fills a diesel Volkswagen Tiguan for the first time. Add a back seat full of kids, a phone call or rain, and habit wins.
Naunton Park drivers: how to avoid petrol in a diesel next time
- Green for unleaded and black for diesel is normal in the UK — yet not on each forecourt. Go by the label on the pump, not the colour.
- The first fill in a strange motor is the time to check the filler flap — on it, or on the cap, plenty of motors state which fuel they take.
- Good intentions count for less than a sticker or a fob in a bright colour on your diesel's key if a house has one of each. So mark it.
- "Diesel", aloud, before you pick up the nozzle — each time a new or hired car needs its first tank. It seems daft. It does the trick.
- Mistakes like this are simple to make while your mind is on something else, so your phone goes away.
- Some diesels come with a filler designed to reject a petrol nozzle, and devices you can add exist for vehicles without one. Such an inhibitor helps up to a point — as a safety net, not a reason to stop reading the petrol pump.
- Less petrol makes a thinner mixture, so stop the moment you realise — though remembering that your next step is unchanged. It is still not to fire it up.
Put petrol in a diesel around Naunton Park already?
Short and simple, then, is the order of things. Don't fire it up, and don't turn your ignition on. If you are still at the forecourt — Esso or anywhere else — ask the staff to help you push the vehicle away from the pump. Ring 0333 366 0103 next, with three facts — the fuel, the approximate amount, and whether it has run.
If it was AdBlue and not petrol, say so. That's a different issue — corrosion and deposits instead of lost lubrication — and it has its own page for Naunton Park.
One petrol in a diesel job in Naunton Park costs more than another. Why?
There is no fair single quote for this, because the four situations above are four different jobs. Chiefly, your cost moves with which one you're in. The ratio counts next, meaning how much of your tank is petrol, followed by the position of your car and whether reaching it is safe for our van.
Before any quote, not after, come three questions: the fuel that got in, the volume, and whether it's run. That's why. Their answers are what change a range into one firm number.
About Naunton Park and its setting
Naunton Park is a suburban area located on the outskirts of Gloucester, situated near the River Severn in Gloucestershire. Naunton Park sits at an elevation of 84 metres, with a mix of housing types, although detached homes are predominant. Naunton Park is close to nearby places such as Charlton Park and Moor End, and is within a short distance of Gloucester city centre.
Fuel drain cover across Gloucestershire, Naunton Park included
Charlton Park, Moor End and Sandy Lane are among the locations near Naunton Park that the same vans work, answering petrol in diesel jobs across Naunton Park's GL postcode area. A forecourt, a supermarket car park, a lay-by or your own driveway are all spots our engineers work, and the vehicle does not need to move to us.
In Naunton Park and still at the petrol pump?
In that case, you could not be in a better spot. Keep it turned off, then ring.