Silksworth: Petrol in a Diesel Car? How Worried to Be
Provided it has not been started, you can worry far less than you probably are. Until the ignition primes the pump, the starter cranks, or the vehicle is driven, petrol in a diesel tank simply rests there and does nothing. Which means the truthful reply to that first Silksworth question — "have I ruined it?" — usually no. To leave the vehicle like that, call Petrol in Diesel then leave the motor alone. What petrol really does to a diesel, how to judge how far it has travelled, and how to keep it from happening again: that's the remainder of this page.
Petrol in a diesel: what does it do to your engine?
Diesel has two jobs on its way through a motor. Lubricating comes before burning; it does both. Your high-pressure pump and the fuel injectors are designed to extremely fine clearances, and the diesel passing through them is what keeps those surfaces from wearing against one another.
Petrol handles the first task badly and the second not at all. A pump running on a petrol mix is wearing itself out, since petrol is runnier than diesel and strips out the lubrication your fuel system depends on. Petrol is also designed to resist igniting under compression — the reverse of what a diesel wants from its fuel — and that's where any knocking comes.
Put those together and the shape of the trouble is clear. Not contact but movement is what does the damage. Where the petrol is only inside your tank, it's a fault of fuel, nothing more. A pump that has been working on that petrol is the beginning of a mechanical one, and whatever a worn pump sheds travels on with your fuel to your injectors downstream.
Four situations we see in Silksworth: how serious is petrol in a diesel?
Filled but not once started — the best it gets. Just that tank has petrol in it, and so the task is clearing your tank and purging the fuel system where the car stands. This situation can only really take place on a forecourt: anywhere else, the vehicle got there by being driven.
A moment's running, or merely your ignition on. Once primed, the system has drawn petrol out of that tank up to the filter and your lines. Still normally straightforward: drain, flush, and your filter sorted.
Driven a few miles. Now your pump has spent those miles labouring on diluted fuel. Miles is only half of that; how hard it was driven counts equally. Either way the work runs to that tank, your lines, the filter and clean fuel through the entire circuit. Short trips, like the school run to Mill Hill Primary School, are one thing. Driving as far as Sunderland, under 3 miles away, makes a very different job — as does any distance on the A1(M), under 5 miles from Silksworth, with the motor running hard all the way.
Driven on until it complained — rattling, smoke, a lumpy idle, a dead throttle. The engine is telling you your fuel is no longer acting like diesel. Whether it is the verge on Silksworth Lane, a lay-by or a side street, stop there and leave it. A vehicle stopped quickly very rarely has permanent damage, because the fuel drain and the flush, which still go first, deal with it.
What Silksworth motorists get told about petrol in a diesel — and the myths in it
Myth: topping up to full with diesel makes it fine. It does not. Nothing comes out when you top up — the tank just carries more of the same blend. Percentage is not how a diesel fuel system copes with petrol, whatever that advice assumes.
Myth: a modern diesel copes with a bit of petrol. If anything, the opposite. At higher pressure, through more precise components: that's how a newer diesel handles its fuel, and so the protection counts more, not less.
Myth: "If it starts and drives, there is no harm done." This is the one that catches drivers. The driver of a petrol motor fed diesel normally stops, because it will not run, and the damage stops with them. Nothing seems to have happened when a diesel fed petrol fires up, ticks over and drives away, as it usually does; meanwhile the pump wears. Being able to run is not proof of being fine.
Not so: a two-stroke additive makes it safe to drive home. It is an old fix, supposed for another issue. It doesn't put back what petrol has weakened, and the petrol is still in that tank afterwards.
"Drain it yourself and you are sorted" — a myth, since 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. Draining petrol into a can at the roadside is also really hazardous.
How petrol ends up: petrol in a diesel
Nobody does it on purpose, and it is rarely carelessness. One way only, because of the nozzles: the slimmer petrol one slips inside a diesel filler with almost no resistance, whereas the diesel one mostly will not fit a petrol vehicle. That is how the forecourt makes it easy.
It takes place when habit and the vehicle stop matching. A new car, a hire car or a courtesy car. Two vehicles on one drive, one petrol, one diesel. A forecourt you know, but with its pumps laid out differently. Racing for a train outside Sunderland and filling up en route. A new-to-you diesel Renault Megane, its first fuelling, and a driver used to petrol: exactly when it happens. Throw in rain, a phone call or a back seat full of children, and your hand does what it has always done.
How to avoid petrol in a diesel at your next fill-up around Silksworth
- A green handle for unleaded and black for diesel is normal in the UK — but not on each forecourt. Go by the label on the petrol pump, not the colour.
- Inspect the filler flap. Many cars state the fuel type inside the flap or on the cap. Look at it on the first fill in any vehicle 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 meaning to remember.
- Say it before you lift it. On the first fill in a new or hired car, say "diesel" aloud before you take the nozzle off the petrol pump. It seems daft and it does the trick.
- Mistakes like this are simple to make while your mind is on something else, so your phone goes away.
- Add-on devices exist for vehicles without one, and some diesels come with a filler that will not accept a petrol nozzle. Useful — but a safety net only, never a reason to stop checking the label.
- As soon as you realise, stop: less petrol in your tank means a weaker blend. What to do next doesn't change, though — still don't fire it up.
Silksworth: already put petrol in a diesel?
The order of things is short, then. Starting it is out, and so is turning on your ignition. If you are still on the forecourt — Morrisons or anywhere else — ask the staff to help you roll it clear of the petrol pump. What got in, roughly how much, and if it's run: tell us those when you phone 0333 366 0103.
Corrosion and deposits are the trouble with AdBlue, whereas petrol brings lost protection. So if it was AdBlue, say so — and see its own Silksworth page.
Silksworth petrol in a diesel tasks: why one costs more than another
There is no fair single price for this, since the four scenarios above are four separate tasks. Mostly, the cost shifts with which one you are in. Two things come after that: the petrol that got in as a share of what that tank holds, then the spot the vehicle is in and whether a van can reach it safely.
Before any quote, not after, we ask three questions: the fuel that was put in, its volume, and whether it's run. That's why. Those answers are what change a range into one firm number.
About Silksworth and where it is
Silksworth is a suburban area located on the outskirts of Sunderland in Tyne and Wear, situated near the coast at an elevation of 89 metres. Silksworth sits close to nearby places such as Moorside and Sourmilk Hill, and is characterized by its predominantly semi-detached housing stock. Silksworth is part of the larger Sunderland urban area, with the city centre just 2.6 miles away. Silksworth has a population of approximately 4977 residents.
Silksworth and Tyne and Wear: where our fuel drain cover runs
Moorside, Sourmilk Hill and Farringdon are among the locations near Silksworth that the same teams work, answering petrol in diesel call-outs across Silksworth's SR postcode area. The car does not need to move to us: we drain on a forecourt, in a supermarket car park, in a lay-by or on your own drive.
In Silksworth and still at the petrol pump?
Then you are in the best position there can be. Leave the vehicle turned off, then ring.