Petrol in a Diesel Car in Sawley: How Worried Should You Be?
Far less than you likely are, if it has not been started. "Have I wrecked it?" is the first question everyone in Sawley asks, and the truthful answer is normally no, because petrol resting in a diesel tank hurts nothing until it's drawn through the fuel system — by ignition priming, by your starter, or by being driven. Petrol in Diesel is who to call, with your engine kept off, and so it stays that way. Read on for three things: the effect petrol has inside a diesel engine, the signs of how far it has got, and ways to make sure you don't repeat it.
Inside the motor: what petrol in a diesel really does
Diesel does two tasks on its way through an engine. Lubricating comes before burning; it does both. Your high-pressure pump and your injectors are designed to extremely fine clearances, and the diesel passing through them is what stops those surfaces from wearing down against each other.
Of those two tasks, petrol manages the first badly and the second never. It's thinner than diesel and takes away the protection the system depends on, so a pump running on a petrol mix is a pump wearing itself. And petrol is designed to resist igniting under compression, which is the reverse of what a diesel needs from its fuel. That is where the clattering comes from.
Taken together, they show the shape the issue takes. Contact doesn't do the harm — movement does. Where the petrol is only inside the tank, it's an issue of fuel, nothing more. A pump that has been labouring on that petrol is the start of a mechanical one, and whatever a worn pump sheds moves on with the fuel to the injectors downstream.
Sawley, petrol in a diesel: four cases, from mild to major
Fuelled but never started — the best it gets. On a forecourt, and truly only there, that petrol is still confined to your tank — because everywhere else your car was driven to get to it. The job is draining and flushing on the spot.
Ignition on, or started for a second. The system has been bled, so petrol has left that tank and reached the filter and your lines. Drain, flush, deal with your filter: still normally simple.
Those few miles driven were your pump working on fuel thinned by petrol throughout. How hard the car was driven counts as much as how far, and the work covers that tank, the lines, the fuel filter and clean fuel through the whole system. A school run to Sawley Infant and Nursery School is one thing. A run as far as Derby, under 10 miles away, is a very different job. So is any mileage on the M1, under a mile from Sawley, where the engine has been labouring hard the whole time.
It protested, and only then stopped: smoke, clattering, a throttle gone soft, an idle gone ragged. The engine is telling you your fuel is no longer behaving like diesel. Stop where you are — on the verge on Plant Lane, at the kerb, down a side road — and do not move it again. A car stopped early very seldom has lasting damage, as the fuel drain and the flush, which still come first, take care of it.
What Sawley people get told about petrol in a diesel — and the stories in it
It will not be fine. The myth: "Fill it the rest of the way with diesel and it will be." A fuller tank of the same mix is all you get, because topping up takes out nothing. A diesel fuel system doesn't accept petrol by percentage in the way that advice presumes.
"Newer diesels can handle a little petrol" — a myth, and nearer the reverse. A modern diesel runs its fuel through smaller components at higher pressure, which makes the lubrication matter more, not less.
"It starts, it drives, so no harm done" — the myth that trips up more motorists than any other. The motorist of a petrol motor fed diesel normally has no choice but to stop, because it will not run, and the harm stops with them. Feed petrol to a diesel and it normally starts, idles and pulls away as if nothing happened — all the while its pump wears. Fine and running aren't the same thing.
An old workaround for a separate issue is behind this one. Myth: "Add some two-stroke oil and drive the car home." It doesn't put back what petrol has thinned, and that petrol is still in your tank later.
Myth: "Drain the tank yourself and you are sorted." Once the engine has been run, some of the petrol is no longer in the tank: it is in the fuel filter and your lines, and it goes right back through the pump at your next start. And, a can of petrol filled at the kerbside is truly hazardous.
Why petrol in a diesel happens at all
It's rarely carelessness, and no one does it on purpose. The forecourt makes it easy: the petrol nozzle is the narrower of the two, and it slips into a diesel filler with almost no resistance, while a diesel nozzle generally will not go into a petrol vehicle at all. So the slip runs one way.
When habit and your car stop matching, it happens. Courtesy car, hire car, or a vehicle that's new. Two motors on one drive, one petrol, one diesel. Your usual forecourt, its pumps suddenly in a different order. A train to catch, and a rushed fill on the way to Long Eaton. Precisely the moment it happens: after years of driving petrol, a driver fills a diesel Renault Megane for the first time. With rain, a call coming in, or a car full of children to deal with, the hand simply does what it always has.
Next time you fill up in Sawley: avoiding petrol in a diesel
- Not every forecourt in the UK keeps to green for unleaded and black for diesel, though most usually do. Read the pump's label; the colour is only a hint.
- Check the filler flap. Many vehicles state the fuel type inside the flap or on the cap. Look at it on your first fill in a vehicle you do not know.
- Good intentions do less than a sticker or a fob in a bright colour on the diesel's key when a home has one of each. So label it.
- It sounds silly and it works: on your first fill in a new or hired car, say "diesel" aloud before you take the nozzle off the pump.
- While you're thinking about something else, this is an easy mistake to make — so put your phone away.
- Some diesels have a filler built to refuse a petrol nozzle, and devices you can add exist for motors without one. Such an inhibitor helps up to a point — as a safety net, not a reason to stop checking the petrol pump.
- The moment you notice, stop: less petrol in your tank means a thinner mix. What to do next doesn't change, though — still do not start it.
Petrol already in a diesel around Sawley? Begin here
Then the order of things is brief. Do not switch the ignition on, and don't start it. The staff at the forecourt — whether at Texaco itself or wherever you filled up — will normally help roll it away from the pump if you ask. Next, 0333 366 0103. We'll ask what got in, roughly how much, and if it has been run.
If it was AdBlue and not petrol, say so. That's a separate issue — corrosion and deposits rather than lost protection — and it has its own page for Sawley.
What makes one Sawley petrol in a diesel task cost more than the next
Four different jobs lie behind the four scenarios above — which is why there is no honest single price. Mostly, your cost shifts with which one you are in. The proportion matters next, meaning how much of your tank is petrol, and then the position of the car and whether getting to it is safe for our van.
Three questions come first, before any quote, rather than after — what got in, how much, has it run — and that is the reason. A range turns into a straight figure when the answers are in.
About Sawley
Sawley is a suburban area in Derbyshire, situated on the banks of the River Trent at an elevation of around 33 metres. Sawley lies approximately 8 miles south of Derby and 107 miles north of London, with nearby places including New Sawley, Trentlock, and Breaston. Sawley has a population of around 4293 people and is characterised by its predominantly semi-detached housing stock. Sawley's riverside setting provides a distinctive feature of the area.
Fuel drain cover around Sawley and across Derbyshire
Sawley waits in the NG postcode area, and our vans that answer petrol in diesel calls there work the places around it as well — New Sawley, Trentlock and Breaston among them. No need to move your vehicle to us. Forecourts, supermarket car parks, lay-bys and your own driveway are all locations where we work.
Sawley: still at the petrol pump?
No position is better: that's where you now are. Keep it off. Ring.