Should You Worry? Petrol in a Diesel Car in Chyandour
Probably less than you already are — provided nobody has started the vehicle. Everyone in Chyandour begins with "have I ruined it?", and the fair answer is generally no: petrol left in that tank of any diesel stays harmless till priming, cranking or driving draws it into the system. To keep the vehicle that way, ring Petrol in Diesel and leave the motor switched off. Read on for three things: the effect petrol has inside a diesel engine, the clues of how far it has got, and the way to make sure you never repeat it.
What petrol in a diesel does to the engine
Diesel does two tasks on its way through an engine. Oiling comes before burning; it does both. The high-pressure fuel pump and your injectors are made to very fine gaps, and your diesel passing through them is what keeps those surfaces from wearing against one another.
The second task petrol does not do at all, and the first it does badly. Being less viscous than diesel, petrol strips away the lubrication a fuel system needs, so a pump running on the mixture to wear itself. It is equally made to resist igniting under compression — the reverse of what a diesel needs — which is why you hear the knocking.
Seen together, they make clear the shape the trouble takes. Not contact but movement is what causes the damage. Petrol in a tank is a fuel issue. Once the pump has been running on that petrol, a mechanical issue has begun: anything shed by a pump that's wearing down travels onward to your injectors with your fuel.
How bad is petrol in a diesel? Four situations we see in Chyandour
Fuelled, and not started: nothing beats it. The petrol is in your tank and just your tank, and the task is a drain and a flush where the vehicle sits. This is the one situation that can only really happen at a forecourt, since anywhere else your car has been driven to get there.
Started for a second, or just your ignition on. Once primed, the system has pulled petrol out of that tank up to the filter and the lines. Still generally straightforward: drain, flush, and your filter sorted.
Your pump now worked a few miles on diluted fuel — that is what driving the vehicle meant. The work is that tank, your lines, your filter and fresh fuel through the entire system, and how hard the car was driven matters as much as how far. The school run to Gulval School is one thing. Very different once more: a trip to Truro, under 25 miles away, or some miles on the M5, over 50 miles from Chyandour, where the motor never stopped running hard.
Knocking, a ragged idle, smoke, a throttle gone soft: driven till it complained. The fuel is not behaving like diesel any more, and the engine is telling you. Whether it's the verge on Jelbert Way, a lay-by or a side street, stop there and leave it. A vehicle stopped quickly very rarely has lasting damage, since the fuel drain and the flush-through, which still come first, sort it out.
What Chyandour people get told about petrol in a diesel — and the myths in it
It will not be fine. The myth: "Fill it the rest of the way with diesel and it'll be." Nothing is removed when you top up — your tank just carries more of the same blend. Percentage isn't how a diesel fuel system tolerates petrol, whatever that advice assumes.
If anything, the reverse holds. Myth: "A current diesel can cope with a bit of petrol." Protection matters more on current diesels, not less, since their fuel passes through more precise components at higher pressure.
"It starts, it drives, so no harm done" — the myth that trips up more people than any other. The motorist of a petrol engine fed diesel normally stops, since it will not run, and the damage stops with them. While the pump wears, a diesel fed petrol usually starts, idles and drives away as though nothing has happened. Running is not the same as fine.
Not so: a two-stroke additive lets you to drive home. It is an old fix, meant for another fault. It does not put back what petrol has weakened, and that petrol is still in your tank after that.
Myth: "Drain the tank yourself and you are sorted." After the motor has been run, some of that petrol is no longer in the tank: it is in the fuel filter and the lines, and it goes straight back through your pump on your next start. On top of that, petrol drained into a can by the road is genuinely dangerous.
How it happens: petrol in a diesel
No one does it on purpose, and it is seldom carelessness. The petrol nozzle is the slimmer 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 simple, and the slip runs one way.
Habit and your car getting out of step is when it happens. A motor that is new to you — a hire car, on loan as a courtesy car, or brand new. Households running one of each, petrol and diesel. A familiar forecourt with the pumps in a different order. Filling up in a rush en route to Penzance, with a train to catch. The first fill-up in a diesel Volkswagen Golf after years of driving petrol is precisely 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.
Next time you fill up in Chyandour: avoiding petrol in a diesel
- The label is what counts, so check the pump rather than the colour: in the UK unleaded handles are normally green and diesel black, yet not on each forecourt.
- Inspect your filler flap. Many cars state the fuel inside the flap or on the cap. Look at it on your first fill in a car you do not know.
- Label the key. In a household with one of each, a coloured fob or a sticker on the diesel's key does more than any amount of intending to remember.
- Say it before you lift it. On your first fill in a new or hired car, say "diesel" out loud before you take the nozzle off the pump. It sounds silly and it works.
- Mistakes like this are easy to make whilst your mind is on something else, so the phone goes away.
- Up to a point, a misfuel inhibitor helps: some diesels come with a filler designed to reject a petrol nozzle, and add-on devices are available for the remainder. Count it as a backstop, and keep checking the pump.
- The moment you realise, stop: less petrol inside the tank means a thinner blend. What to do next doesn't change, though — still do not fire it up.
Chyandour: already put petrol in a diesel?
Short and simple, then, is the order of things. Starting it is out, and so is switching on your ignition. The staff at the forecourt — whether at Tesco itself or wherever you filled up — will normally help push it away from the petrol pump if you ask. Call 0333 366 0103 next, with three facts — your fuel, the rough amount, and whether it's run.
Say so if it was AdBlue instead of petrol: it is a different issue, with its own page for Chyandour, since AdBlue brings corrosion and deposits rather than lost protection.
One petrol in a diesel task around Chyandour costs more than another. Why?
The four scenarios above are four different jobs, so no single price for this would be honest. What moves your cost is chiefly which of them you're in. Where the car is counts too, and whether our van can safely get to it, after the share of petrol to what your tank holds.
What was put in, how much, and whether it has run — three questions we ask before costing, not after, for precisely that reason. Given the answers, there is a straight figure rather than a range.
About Chyandour itself
Chyandour is a small suburban area in Cornwall, situated on the coast with an elevation of around 4 metres. Chyandour lies near the villages of Gulval and Penzance, and is part of the wider Penwith district. Chyandour has a mix of housing types, with semi-detached homes being the most common. Chyandour is located approximately 22.9 miles from Truro, the nearest city.
Fuel drain cover across Cornwall, Chyandour included
Gulval, Trythogga and Trevarrack are among the locations near Chyandour that the same vans work, answering petrol in diesel call-outs across Chyandour's TR postcode area. We drain wherever your vehicle is — your own driveway, a lay-by, a supermarket car park, a forecourt — so it does not have to come to us.
Chyandour: still at the petrol pump?
In that case, you couldn't be in a better spot. Turned off it stays; then call.