Snitterfield: Petrol in a Diesel Car? How Worried to Be
Provided it has not been started, you can worry far less than you probably are. Everyone around Snitterfield begins with "have I ruined it?", and the honest answer is usually no: petrol left in that tank of any diesel remains harmless until priming, cranking or driving draws it into your fuel system. Petrol in Diesel is who to ring, with the motor left off, and so it stays that way. Below, this page sets out what petrol actually does inside a diesel, how far it may have got, and how to stop it happening to you a second time.
Petrol in a diesel: what does it do to your engine?
Passing through a motor, diesel does two things at the same time. It combusts, and before it ignites it protects. The high-pressure pump and the injectors are made to very fine clearances, and the diesel passing through them is what stops those surfaces from wearing against one another.
Of these two jobs, petrol handles the first poorly and the second never. Being less viscous than diesel, petrol strips away the protection a fuel system needs, so a pump on the mixture to wear itself. It's also made to resist igniting under compression — the opposite of what a diesel needs — which is why you get the rattling.
Combined, those leave the shape of the problem plain. The harm is done by movement, not by contact. Petrol in a tank is a fuel issue. Whatever a worn pump sheds goes on, carried by your fuel, into your injectors further along, which is why a pump that has worked on that petrol is where a mechanical problem begins.
Petrol in a diesel around Snitterfield: how serious is it? Four cases
Fuelled but not once started — the best it gets. Just that tank has petrol in it, and so the task is draining your tank and flushing your system where the vehicle sits. This situation can only truly take place at a forecourt: anywhere else, the car got there by being driven.
Your ignition turned on, or a short start. The fuel system has been bled, so petrol has left the tank and got to the fuel filter and the lines. That is usually still an easy task — a drain, a flush, and the filter seen to.
Driven a couple of miles. Now your pump has spent these miles working on diluted fuel. How hard your car was driven counts as much as how far, and this work covers the tank, your lines, the filter and clean fuel through the entire circuit. Driving the children to Snitterfield Primary School is one kind of trip. A run as far as Coventry, under 15 miles away, is a very different job. So is any distance on the M40, under 3 miles from Snitterfield, where the engine has been labouring hard throughout.
Driven till it complained. Rattling, a lumpy idle, smoke, a throttle that has gone soft. That's the motor telling you its fuel no longer is behaving like diesel. Leave it wherever it has stopped: a lay-by, a side street, the verge on Smiths Lane. Lasting damage is very unusual if a vehicle is stopped early, and the fuel drain and flush that still go first take care of it.
Myths Snitterfield motorists hear about petrol in a diesel
"Top it up the rest of the way with diesel and it will be fine" — a myth. It won't. Nothing is removed by topping up — you're left with a fuller tank, still the same mix. That guidance supposes a diesel fuel system tolerates petrol by percentage. It doesn't.
Myth: "A newer diesel can cope with a bit of petrol." If anything, the reverse. More precise components and higher pressure are the way a newer diesel runs its fuel, and that makes the protection count more, not less.
Myth: "If it starts and drives, there is no harm done." This is the one that catches motorists. Feed diesel to a petrol motor and it normally won't run, and so the motorist stops — and the damage stops with them. A diesel fed petrol generally starts, idles and drives away as though nothing has happened, whilst your pump grinds. Fine and running aren't the same thing.
An outdated workaround for a distinct fault is behind this one. Myth: "Add some two-stroke oil and drive it home." What petrol has weakened remains weakened, and the petrol stays inside that tank anyway.
Myth: "Drain your tank yourself and you're sorted." After your engine has been run, some of that petrol is no longer inside that tank: it is in the fuel filter and the fuel lines, and it goes straight back through the pump on the next start. It is also genuinely hazardous to drain petrol into a can at the kerbside.
Why petrol in a diesel takes place at all
Carelessness is seldom the cause, and no one means to do it. 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, whilst a diesel nozzle generally will not go into a petrol car at all. So the error runs one way.
Routine and the vehicle falling out of step is how it occurs. Courtesy car, hire car, or a vehicle that's brand new. Two vehicles on one driveway, one petrol, one diesel. Your usual forecourt, its pumps now in a different order. A rushed fill on the way to Bearley with a train to catch. Exactly the moment it takes place: after years of driving petrol, a driver fills a diesel Volkswagen Golf for the first time. With rain, a call coming in, or a car full of children to deal with, the hand just does what it always has.
Avoiding petrol in a diesel next time you fill up in Snitterfield
- The label is what counts, so read the pump rather than the colour: in the UK unleaded handles are usually green and diesel black, but not on each forecourt.
- Check your filler flap. Plenty of cars state the fuel inside the flap or on the cap. Look at it on your first fill in any motor you do not know.
- A coloured fob or a sticker on the diesel's key does more than any amount of intending to remember, in a home with one of each.
- Before the nozzle leaves the pump the first time you fuel a hired or new vehicle, say "diesel" aloud. Daft, yes, yet it works.
- Mistakes like this are straightforward to make whilst your mind is on something else, and so the phone goes away.
- Up to a point, a misfuel inhibitor helps: some diesels have a filler built to refuse a petrol nozzle, and aftermarket devices are available for the remainder. Treat it as a backstop, then keep reading the petrol pump.
- Less petrol means a thinner blend, so stop the moment you realise — while remembering that the next stage is unchanged. It is still not to fire it up.
Petrol already in a diesel in Snitterfield? Begin here
Then the order of things is brief. Leave it unstarted, with the ignition switched off as well. Ask the staff to help you roll it clear of the pump if you're still at the forecourt, whether that is Tesco or anywhere else. Ring 0333 366 0103 next, with three facts — the fuel, the approximate amount, and if it has run.
AdBlue, not petrol? Then say so. Corrosion and deposits, not lost lubrication, make it a different problem — Snitterfield has a page just for it.
One petrol in a diesel job in Snitterfield costs more than another. Why?
There's no fair single price for this, since the four scenarios above are four different jobs. Chiefly, your cost moves with which one you're in. Two things come after that: the petrol that went in as a proportion of what that tank holds, then the place the car is in and whether a van can get to it safely.
What went in, how much, and whether it's run — three questions we ask before costing, not after, for exactly that reason. Given those answers, you get a straight figure rather than a range.
About Snitterfield, briefly
Snitterfield is a small village in Warwickshire, situated in the West Midlands region of England, with a population of around 665 people. Snitterfield sits at an elevation of 85 metres, approximately 14 miles from Coventry and 83 miles from London. Snitterfield is characterized by its predominantly detached housing and surrounding countryside, near to places like Heath End and Black Hill. Snitterfield remains a quiet, rural community with a strong sense of local identity.
Fuel drain cover across Warwickshire, Snitterfield included
Heath End, Black Hill and Wolverton are among the spots near Snitterfield that the same vans work, answering petrol in diesel call-outs across Snitterfield's CV postcode area. You need not move your vehicle to us. Forecourts, supermarket car parks, lay-bys and your own driveway are all places we drain.
Still at the petrol pump around Snitterfield?
No position is better: that is where you now are. Keep it switched off, then ring.