How Worried Should You Be? Petrol in a Diesel Car in Swalecliffe
Not started? Then less anxious than you probably feel. Petrol resting in a diesel tank does nothing to your engine until something pulls it through the fuel system — your ignition priming your pump, your starter, or driving on its own. So the honest answer to the first query everyone around Swalecliffe asks, "have I ruined it?", is generally no. To leave the car like that, phone Petrol in Diesel and leave the motor switched off. What petrol really does to a diesel, how to gauge how far it has gone, and how to keep it from happening a second time: that is the rest of this page.
The engine and petrol in a diesel: what happens
Two tasks fall to diesel on its journey round a motor. It burns, and before it burns it protects. What stops the surfaces inside the high-pressure fuel pump and the fuel injectors from wearing down against each other is your diesel flowing through them — they're built to extremely fine tolerances.
The second task petrol doesn't do at all, and the first it does badly. It's runnier than diesel and strips away the protection your fuel system rests on, and so a pump running on a petrol mixture is a pump wearing itself. And petrol is designed to resist igniting under compression, which is the opposite of what a diesel needs from its fuel. That is where the knocking comes from.
Combined, those make the shape of the trouble clear. Not contact but movement is what does the damage. Petrol in the tank 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 fault begins.
How bad is petrol in a diesel? Four situations our engineers see in Swalecliffe
Filled but never started — the best it gets. On a forecourt, and really only there, the petrol is still limited to the tank — since everywhere else the car was driven to get to it. The job is draining and flushing on the spot.
Ignition on, or started for a moment. Your system has been bled, so petrol has left that tank and reached the filter and the lines. Normally nothing more than clearing, purging and sorting the fuel filter, and so still straightforward.
The pump has spent a few miles on weakened fuel — that's what driving the vehicle meant. The work is the tank, the fuel lines, the fuel filter and fresh fuel through the whole system, and how hard the car was driven matters as much as how far. A school run to Swalecliffe Community Primary School is one matter. Driving as far as Canterbury, under 10 miles away, makes a very different job — as does any distance on the M2, under 10 miles from Swalecliffe, with the engine labouring hard all the way.
It complained, and only then stopped: smoke, rattling, a throttle gone soft, an idle gone uneven. That's your motor telling you its fuel has stopped behaving like diesel. Leave it where it has stopped: a lay-by, a quiet street, the verge on Edgar Close. The drain and flush-through still come first, and they take care of it: when a car is pulled over early, permanent damage is very unusual.
Stories Swalecliffe people hear about petrol in a diesel
"Top it up the rest of the way with diesel and it'll be fine" — a myth. It will not. Topping up removes nothing; it gives you a bigger tank of the same mix. A diesel fuel system does not tolerate petrol by percentage in the way that advice supposes.
Not so: a current diesel copes with a bit of petrol. Rather, the reverse. A modern diesel sends its fuel through finer components at higher pressure, which makes the lubrication matter more, not less.
One myth that catches motorists out: if it starts and drives, it must be unharmed. The motorist of a petrol motor fed diesel usually has no choice but to stop, since it will not run, and the damage stops with them. A diesel fed petrol usually starts, idles and drives away as if nothing has happened, while your pump wears. Running is not the same as fine.
An old workaround for a separate fault is behind this one. Myth: "Add some two-stroke oil and drive the car home." It doesn't put back what petrol has diluted, and that petrol is still inside that tank later.
"Drain it yourself and you are sorted" — a myth, since after it has been running some petrol lies in the fuel filter and lines, waiting to go straight back through your pump at the next start. Clearing petrol into a can by the roadside is also really risky.
How does petrol in a diesel happen?
No one does it on purpose, and it's rarely carelessness. The forecourt makes it easy: the petrol nozzle is the smaller of the two, and it slips into a diesel filler with almost no resistance, while a diesel nozzle mostly won't go into a petrol motor at all. So the mistake runs one way.
It occurs when routine and your car stop matching. A new vehicle, a hire car or a courtesy car. A household with one petrol and one diesel on the driveway. A familiar forecourt with the pumps in a different order. Filling up in a rush en route to Chestfield & Swalecliffe, with a train to catch. The first fill-up in a diesel Volkswagen Golf after years of driving petrol is exactly the moment it takes place. Throw in rain, a phone call or a back seat full of children, and the hand repeats what it has always done.
How to prevent petrol in a diesel at your next fill-up around Swalecliffe
- Not every forecourt in the UK follows green for unleaded and black for diesel, though most usually do. Check the petrol pump's label; the colour is only a hint.
- The first fill in an unfamiliar motor is the time to check your filler flap — inside it, or on the cap, plenty of cars state which fuel to use.
- Good intentions count for less than a sticker or a fob in a vivid colour on the diesel's key when a household has one of each. So label it.
- Say it before you lift it. On the first fill in a new or hired car, say "diesel" out loud before you take the nozzle off the petrol pump. It sounds silly and it does the trick.
- Tuck your phone away. This is an easy mistake to make whilst you are thinking about something else.
- Add-on devices are available for motors without one, and some diesels are built with a filler that won't accept a petrol nozzle. Useful — but a safety net at best, never a reason to stop checking the label.
- The moment you realise, stop: less petrol in that tank makes a thinner mixture. What to do next doesn't change, though — still don't start it.
Swalecliffe: already put petrol in a diesel?
In that case, there is just a short order of things. Do not start the car, and don't turn your ignition on. Still on the forecourt, at Esso or anywhere else? Ask the attendants to help you push the car clear of the pump. Next, 0333 366 0103. We will ask what got in, about how much, and if it's been run.
Say so if it was AdBlue instead of petrol: it's a separate problem, with its own page for Swalecliffe, because AdBlue brings corrosion and deposits instead of lost lubrication.
Swalecliffe petrol in a diesel jobs: why one costs more than another
Four different jobs sit behind the four scenarios above — which is why there is no honest single price. Which of them you are in is mostly what shifts the cost. Two things follow that: the petrol that was put in as a share of what that tank takes, then the place the vehicle is in and whether a van can reach it safely.
That is why our engineers ask three questions before quoting rather than after: what was put in, how much, and whether it has run. A range turns into a straight figure once those replies are in.
About Swalecliffe, for a moment
Swalecliffe is a coastal suburban area in Kent, situated near the city of Canterbury and overlooking the Thames Estuary. Swalecliffe has a relatively low elevation of around 7 metres above sea level and is close to nearby places such as Chestfield and Tankerton. Swalecliffe is characterised by its predominant semi-detached housing stock and is home to a population of approximately 2803 residents. Swalecliffe is also within commuting distance to London, being around 52.6 miles away.
Fuel drain cover around Swalecliffe and across Kent
Chestfield, Studd Hill and Tankerton are among the locations near Swalecliffe that the same vans work, answering petrol in diesel calls across Swalecliffe's CT postcode area. The car doesn't need to come to us: our technicians drain at a forecourt, in a supermarket car park, in a lay-by or on your own driveway.
At the pump around Swalecliffe, still?
The best spot there is, then — that is where you are. Keep it turned off, then ring.