Petrol in a Diesel Car in Send: How Worried Should You Be?
Provided it has not been started, you can worry less than you likely are. "Have I wrecked it?" is the first thing everyone around Send asks, and the honest answer is normally no, because petrol resting in a diesel tank hurts nothing till it's dragged through the system — by ignition priming, by the starter, or by being driven. To keep it like that, ring Petrol in Diesel then leave your engine switched off. Further down, this page sets out what petrol really does inside a diesel, how far it may have gone, and how to stop it happening to you a second time.
Your engine and petrol in a diesel: what goes on
Two tasks fall to diesel on its route round a motor. Lubricating comes before burning; it does both. Your high-pressure pump and the injectors are made to very fine clearances, and the diesel passing through them is what stops those surfaces from grinding against each other.
Of these two jobs, petrol manages the first badly and the second never. A pump working on a petrol mix is wearing itself out, since petrol is runnier than diesel and strips out the protection 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 is where the rattling comes.
Put those together and the shape of the trouble is plain. Not contact but circulation is what causes the damage. Where that petrol is only in that tank, it is a fault 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 travels on with your fuel to the injectors downstream.
Four situations we see around Send: how bad is petrol in a diesel?
Filled but never started — as good as it gets. Just the tank has petrol in it, and so the task is emptying your tank and flushing the system where the vehicle stands. This situation can only truly occur on a forecourt: anywhere else, your car got there by being driven.
The ignition switched on, or a short start. Once primed, the fuel system has drawn petrol from your tank as far as the filter and the lines. Usually little more than clearing, purging and sorting your filter, so still straightforward.
The pump now worked a few miles on weakened fuel — that's what driving the vehicle meant. The work is that tank, the fuel lines, the fuel filter and fresh fuel through the entire circuit, and how hard the car was driven counts as much as how far. Driving the kids to Send CofE Primary School is one sort of trip. A run as far as Westminster, under 25 miles away, is a very different task. So is any mileage on the M25, under 5 miles from Send, where your engine has been running hard the whole time.
Driven on till it complained — knocking, smoke, a lumpy idle, a soft throttle. The fuel is not acting like diesel any more, and the motor is saying so. Whether it is the verge on Tannery Lane, a lay-by or a side road, stop where you are and leave it. A car stopped soon very seldom has lasting damage, because the fuel drain and the flush, which still come first, take care of it.
Myths Send motorists hear about petrol in a diesel
Myth: "Fill it the rest of the way with diesel and it will be fine." It will not. Nothing comes out when you top up — the tank simply holds more of the same mixture. The assumption behind the guidance — that diesel fuel systems tolerate petrol by percentage — is wrong.
"Newer diesels can handle a little petrol" — a myth, and nearer the reverse. Protection matters more on newer diesels, not less, because their fuel runs through more precise parts at higher pressure.
Myth: "If it starts and drives, there's no damage done." This is the one that catches people. The driver of a petrol engine fed diesel usually has no choice but to stop, because it will not run, and the harm 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. Running is not the same as fine.
An old workaround for a distinct issue lies behind this one. Myth: "Add some two-stroke oil and drive the car home." What petrol has thinned remains weakened, and that petrol stays in your tank regardless.
"Drain it yourself and you are sorted" — a myth, since after it has been running some petrol sits in the filter and lines, ready to go right back through your pump on your next start. Also, a can of petrol drained by the kerbside is truly risky.
How does petrol in a diesel take place?
On purpose? Never. Through carelessness? Rarely, if ever. One way only, since of the nozzles: the slimmer petrol one slips inside a diesel filler with almost no resistance, while the diesel one mostly won't fit a petrol motor. That's how the forecourt makes it simple.
When routine and the car stop matching, it takes place. Any vehicle that is new to you — hired, on loan as a courtesy car, or brand new. Two vehicles on one driveway, one petrol, one diesel. The pumps in a different order on a well-known forecourt. Rushing for a train at Clandon and fuelling up en route. The first fill-up in a diesel Renault Megane after years of driving petrol is exactly the moment it takes place. 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 Send: avoiding petrol in a diesel
- Check the petrol pump, not the colour. In the UK unleaded handles are usually green and diesel black, but not on each forecourt. The label is what counts.
- In a motor you do not know, look inside the flap over the filler or at the cap before the first fill: plenty of vehicles print the fuel there.
- One of each in the home? Mark the key to your diesel — a bright fob, a sticker — since intending to remember is not enough.
- "Diesel", aloud, before you lift the nozzle — every time a new or hired car gets its first tank. It seems silly. It works.
- Tuck the phone away. This is an easy mistake to make while you're thinking about something else.
- A misfuel inhibitor helps, up to a point. Some diesels have a filler built to reject a petrol nozzle, and add-on devices are available for motors without one. They are a safety net, not a reason to stop reading the petrol pump.
- Less petrol means a thinner mixture, and so stop as soon as you realise — though remembering that your next stage is unchanged. It's still not to crank it.
Send: already put petrol in a diesel?
In that case, there's just a short order of things. Leave it unstarted, with your ignition off too. Still on the forecourt, at Shell or anywhere else? Ask the attendants to help you roll it away from the petrol pump. Call 0333 366 0103 next, with three answers — your fuel, the rough amount, and whether it's run.
Corrosion and deposits are the issue with AdBlue, where petrol brings lost lubrication. So if it was AdBlue, say so — and see its own Send page.
What makes one Send petrol in a diesel task cost more than the next
There is no honest single quote for this, since the four scenarios above are four separate jobs. Which of them you're in is mostly what moves your cost. Beyond that it's the ratio — how much petrol was put in against how much that tank holds — and after that where your car is and whether our van can reach it safely.
Ahead of any quote, not after, come three questions: your fuel that got in, the volume, and if it has run. That is why. The answers change a range into a straight figure.
About Send and where it is
Send is a village in Surrey, situated on the banks of the River Wey at an elevation of around 30 metres. Send sits in a rural area near the towns of Woking and Guildford, with nearby places including Cartbridge, Send Marsh, and Old Woking. Send has a population of approximately 1162 people, living in predominantly semi-detached housing. Send is located about 22.9 miles from London, making it a commuter village with easy access to the city.
Fuel drain cover around Send and across Surrey
Cartbridge, Send Marsh and Old Woking are among the locations near Send that the same teams work, answering petrol in diesel calls across Send's GU postcode area. Our engineers drain wherever the car is — your own drive, a lay-by, a supermarket car park, a forecourt — so it never needs to come to us.
Send: still at the pump?
Then you're in the best place there can be. Keep it switched off, and ring.