Petrol in a Diesel Car in Lumley Thicks: How Worried Should You Be?
Not started? Then less anxious than you probably feel. Until the ignition primes the pump, the starter cranks, or the vehicle is driven, petrol in a diesel tank simply sits there and does no harm. Which means the honest reply to the first Lumley Thicks query — "have I ruined it?" — normally no. Leave the motor off then phone Petrol in Diesel — that keeps it that way. Below, you will find what petrol actually does inside a diesel, how far it might have got, and how to stop it happening to you a second time.
Your engine and petrol in a diesel: what happens
Diesel has two tasks on its way through an engine. Oiling comes before burning; it does both. Very fine clearances are built into the fuel injectors and the high-pressure fuel pump, and only the diesel flowing through keeps their surfaces from grinding together.
The second task petrol does not do at all, and the first it does badly. The knocking comes from petrol being made not to ignite when compressed, which is exactly the opposite of what a diesel needs. On top of that it is runnier than diesel, it strips away the lubrication the system rests on, and any pump working on such a mix is wearing itself.
Together, those leave the shape of the issue clear. It is circulation that does the harm, not contact. A tank with petrol in it is a fuel fault. The beginning of a mechanical problem is a pump that has been running on that petrol — and whatever a worn pump sheds travels on with the fuel to the injectors downstream.
Petrol in a diesel around Lumley Thicks: how serious is it? Four cases
The best case there is: filled up, not once started. Only your tank has petrol in it, so the task is emptying that tank and rinsing the system where your car sits. This situation can only really take place at a forecourt: anywhere else, the car got there by being driven.
Ignition on, or started for a second. With the fuel system primed, the fuel lines and filter already contain petrol that has come from that tank. Still generally simple: drain, flush, and the fuel filter sorted.
Those few miles driven meant your pump labouring on fuel weakened by petrol throughout. The work is that tank, your lines, the filter and clean fuel through the entire circuit, and how hard your car was driven matters as much as how far. A school run to Woodlea Primary School is one matter. A run as far as Durham, under 10 miles away, is a very different task. So is any distance on the A1(M), under a mile from Lumley Thicks, where your engine has been working hard the whole time.
Clattering, a lumpy idle, smoke, a throttle gone soft: driven until it complained. The engine is telling you your fuel is no longer behaving like diesel. Pull up wherever you are — the verge on Lumley New Road, a lay-by, a side street — and leave the car where it is. The drain and flush still go first, and they sort it out: when a car is stopped soon, long-term damage is very uncommon.
Lumley Thicks people and the petrol in a diesel myths they hear
"Top it up the rest of the way with diesel and it'll be fine" — a myth. It will not. Nothing is removed by topping up — you're left with a fuller tank, still the same mixture. That guidance supposes a diesel fuel system tolerates petrol by percentage. It doesn't.
Not so: a newer diesel copes with a bit of petrol. If anything, the reverse. At higher pressure, through finer components: that is how a modern diesel handles its fuel, so the protection counts more, not less.
This is the one that catches motorists. Myth: "If it starts and drives, there's no damage done." Diesel in a petrol motor normally leaves a motor that will not run: the driver stops, and so does the damage. Nothing seems to have happened when a diesel fed petrol fires up, ticks over and drives away, as it usually will; meanwhile the pump grinds. Running does not mean fine.
Myth: a two-stroke additive lets you to drive home. It was an old fix, supposed for another issue. What petrol has weakened stays weakened, and that petrol remains in that tank anyway.
"Drain it yourself and you are sorted" — a myth, because after it has been running some petrol sits in the fuel filter and lines, waiting to go right back through your pump at your next start. It is also genuinely dangerous to drain petrol into a can by the roadside.
How it happens: petrol in a diesel
Nobody does it on purpose, and it's rarely carelessness. One way only, because of the nozzles: the smaller petrol one slips inside a diesel filler with almost no resistance, whereas the diesel one generally will not fit a petrol motor. That's how the forecourt makes it easy.
Habit and the vehicle falling out of step is how it happens. A vehicle that is new to you — hired, on loan as a courtesy car, or brand new. One petrol and one diesel on the driveway of the same household. Your usual forecourt, its pumps now in a different order. Filling up in a rush en route to Chester-Le-Street, with a train to catch. Years of petrol motors behind you, a diesel Volkswagen Golf in front of you on the forecourt for its first tank — that is when. Throw in a back seat full of children, a phone call or rain, and the hand takes over.
Next time you fill up in Lumley Thicks: avoiding petrol in a diesel
- Not every forecourt in the UK follows green for unleaded and black for diesel, even if most generally do. Read the pump's label; the colour is only a hint.
- Many cars state the fuel type inside your filler flap or on the cap, so check it on your first fill in a car you do not 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.
- Before the nozzle leaves the pump the first time you fill a hired or new car, say "diesel" aloud. Silly, yes, but it works.
- Mistakes like this are straightforward to make whilst your mind is on something else, and so your phone goes away.
- A misfuel inhibitor helps, up to a point. Some diesels have a filler designed to reject a petrol nozzle, and add-on devices are available for motors without one. They are a backstop, not a reason to stop reading the petrol pump.
- Spotting it mid-fill? Stop at once. A thinner mix results from less petrol inside the tank, but the next step remains the same: do not crank it.
Petrol already in a diesel in Lumley Thicks? Begin here
Then, there is only a short order of things. Do not crank it, and don't switch the ignition on. If you are still on the forecourt — JET or anywhere else — ask the attendants to help you roll the car away from the pump. Call 0333 366 0103 next, with three facts — your fuel, the rough volume, and if it's run.
AdBlue, not petrol? Then tell us. Corrosion and deposits, not lost lubrication, make it a separate fault — Lumley Thicks has a page all for it.
What makes one Lumley Thicks petrol in a diesel task cost more than the next
The four situations above are four different jobs, so no single price for this would be fair. What shifts your cost is chiefly which of them you are in. The proportion matters next, meaning how much of the tank is petrol, and then the position of your car and whether reaching it is safe for our van.
What got in, how much, and whether it's run — three questions our engineers ask before quoting, not after, for precisely that reason. Those replies change a range into a straight figure.
About Lumley Thicks itself
Lumley Thicks is a locality situated on the riverside in County Durham, with an elevation of around 60 metres. Lumley Thicks lies near the city of Durham, approximately 5.4 miles away, and is close to other nearby places such as Woodstone Village and Castle Dene. Lumley Thicks has a population of around 731 people and predominantly features detached housing. Lumley Thicks is located in the North East region of England, about 238 miles from London.
Fuel drain cover across Durham, Lumley Thicks included
Woodstone Village, Castle Dene and Bournmoor are among the places around Lumley Thicks that the same vans work, answering petrol in diesel jobs across Lumley Thicks's DH postcode area. Our engineers drain where your vehicle is — your own driveway, a lay-by, a supermarket car park, a forecourt — so it does not have to come to us.
Lumley Thicks: still at the pump?
No position is better: that is where you are. Keep the vehicle turned off, and ring.