How Worried Should You Be? Petrol in a Diesel Car in Old Haywoods
Unstarted? Then less anxious than you probably are. "Have I wrecked it?" is the first thing everyone in Old Haywoods asks, and the truthful answer is normally no, because petrol resting in a diesel tank harms nothing till it is dragged through the fuel system — by ignition priming, by the starter, or by being driven. Keep it like that: leave the engine off then phone Petrol in Diesel. The remainder of this page sets out what petrol actually does to a diesel, how to tell how far it has got, and how to make sure it does not happen to you a second time.
Inside your engine: what petrol in a diesel does
Passing through a motor, diesel is doing two things at once. Before it ignites, it lubricates — then it burns. The high-pressure fuel pump and the fuel injectors are built to very fine gaps, and the diesel passing through them is what keeps those surfaces from wearing against one another.
Badly at the first, not at all at the second: that is petrol. The knocking comes from petrol being made not to ignite when compressed, which is precisely the reverse of what a diesel needs. On top of that it is runnier than diesel, it strips out the lubrication your system depends on, and any pump working on such a blend is wearing itself.
Taken together, they show the shape the problem takes. The damage is done by circulation, not by contact. Where the petrol is only in that tank, it is a problem 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 fuel injectors further on.
Petrol in a diesel in Old Haywoods: how serious is it? Four cases
The best case there is: filled up, never started. The petrol is in that tank and just that tank, and the job is a drain and a flush where the car stands. This is the one scenario that can only truly happen on a forecourt, because anywhere else the car has been driven to get there.
A brief spell of running, or merely your ignition on. Your system has been primed, so petrol has left your tank and got to your filter and your lines. That's usually still a straightforward task — a drain, a flush, and your filter dealt with.
Driven a couple of miles. Now the pump has spent those miles working on thinned fuel. Miles is only half of it; how hard it was driven counts just as much. Either way the work runs to that tank, your lines, your filter and clean fuel through the entire system. Short trips, such as the school run to Deepcar St John's Church of England Junior School, are one matter. Getting as far as Sheffield, under 10 miles away, makes a very different task — as does any miles on the M1, under 5 miles from Old Haywoods, with the motor running hard all the way.
Driven till it protested. Rattling, an uneven idle, smoke, a throttle that has gone soft. What you are hearing is your motor signalling fuel that no longer acts like diesel. Whether it is the verge on Holling Croft, a lay-by or a side road, stop there then leave it. The fuel drain and flush still come first, and they sort it out: when a vehicle is pulled over early, lasting damage is very uncommon.
Petrol in a diesel myths Old Haywoods people hear
"Top it up the rest of the way with diesel and it will be fine" — a myth. It will not. A fuller tank of the same mix is all it gives, since topping up takes out nothing. Percentage is not how a diesel fuel system copes with petrol, however much that guidance supposes.
Not so: a current diesel copes with a bit of petrol. Rather, the reverse. Protection counts more on modern diesels, not less, since their fuel runs through smaller components at higher pressure.
"It starts, it drives, and so there is no harm" — the myth that catches most people than any other. A petrol motor fed diesel generally won't run, and so the motorist stops and the harm stops with them. While your pump grinds, a diesel fed petrol usually starts, idles and drives away as though nothing has happened. Being able to run isn't the same as being fine.
An old fix for a distinct issue lies behind this one. Myth: "Add some two-stroke oil and drive the vehicle home." The petrol is still in your tank afterwards, and what it has thinned isn't put back.
The next start draws petrol back round the pump from the lines and your filter, where some of it ends up after your engine has run. That's why a DIY tank drain doesn't leave you sorted — a myth. And, a can of petrol drained by the kerbside is genuinely dangerous.
How petrol ends up: petrol in a diesel
Nobody does it on purpose, and it is seldom carelessness. The petrol nozzle is the smaller of the two and slides into a diesel filler with almost no resistance; a diesel nozzle generally won't go into a petrol car at all. The forecourt makes it simple, and the error runs one way.
Routine and the vehicle falling out of step is when it occurs. A new vehicle, a hire car or a courtesy car. Households running one of each, petrol and diesel. Your ordinary forecourt, its pumps now in a different order. A hurried fill en route to Penistone with a train to catch. A new-to-you diesel Volkswagen Golf, its first fuelling, and a driver accustomed to petrol: exactly when it happens. Add rain, a phone call or a back seat full of kids, and the hand repeats what it has always done.
Avoiding petrol in a diesel next time you fill up around Old Haywoods
- Green for unleaded and black for diesel is usual in the UK — but not on each forecourt. Go by the label on the petrol pump, not the colour.
- The first fill in an unfamiliar vehicle is the time to check the filler flap — on it, or on the cap, plenty of vehicles state which fuel to use.
- One of each in the household? Mark your key to the diesel — a bright fob, a sticker — because meaning to remember isn't enough.
- It sounds silly and it does the trick: on your first fill in a new or hired car, say "diesel" aloud before you lift the nozzle off the pump.
- Thinking about something else is when this becomes an easy mistake to make, so tuck your phone away and keep your mind on the petrol pump.
- Some diesels come with a filler built to block a petrol nozzle, and devices you can add exist for cars without one. Such an inhibitor helps up to a point — as a backstop, not a reason to stop reading the petrol pump.
- Less petrol means a thinner blend, so stop the moment you notice — while remembering that your next step is unchanged. It's still not to crank it.
Petrol already in a diesel around Old Haywoods? Start here
Then the order of things is short. Do not switch the ignition on, and don't fire it up. Still on the forecourt, at Murco or anywhere else? Ask the attendants to help you push the vehicle clear of the pump. Then ring 0333 366 0103 and tell us what was put in, roughly how much, and whether it has run.
AdBlue, not petrol? Then tell us. Corrosion and deposits, not lost protection, make it a separate problem — Old Haywoods has a page all for it.
Why one petrol in a diesel job around Old Haywoods costs more than another
There is no fair single price for this, because the four scenarios above are four separate tasks. Which of them you're in is mostly what shifts your cost. Where your car is matters too, and whether a technician can safely get to it, after the share of petrol to what your tank takes.
Three queries come first, before quoting, instead of after — what went in, how much, has it run — and this is the reason. Their answers are what change a range into one firm number.
About Old Haywoods itself
Old Haywoods is a suburban area situated on the riverside in South Yorkshire, with an elevation of 163 metres and a mix of semi-detached housing. Old Haywoods lies approximately 8 miles from Sheffield, and is near other local places such as Wood Royd and Deepcar. Old Haywoods has a population of around 5011 people, and is located about 149 miles north of London. Old Haywoods is characterized by its residential layout and proximity to the river.
Fuel drain cover in Old Haywoods and across South Yorkshire
The vans answering petrol in diesel call-outs around Old Haywoods, in the S postcode area, equally work the locations near it, Wood Royd, Deepcar and Wood Willows included. We drain where your vehicle is — your own drive, a lay-by, a supermarket car park, a forecourt — so it never needs to come to us.
Old Haywoods: still at the petrol pump?
No position is better: that's where you are. Ring, and leave it switched off.