Should You Worry? Petrol in a Diesel Car in White Cross
Likely less than you already are — provided no one has started it. Everyone in White Cross begins with "have I wrecked it?", and the fair answer is normally no: petrol left inside the tank of a diesel stays harmless until priming, cranking or driving draws it into the fuel system. Keep it that way: leave your engine off and phone Petrol in Diesel. The remainder of this page covers what petrol actually does to a diesel, how to judge how far it has got, and how to make sure it does not happen to you a second time.
The engine and petrol in a diesel: what goes on
On its way through a motor, diesel has two tasks. It ignites, and before it combusts it protects. Your high-pressure pump and the fuel injectors are made to very fine tolerances, and your diesel passing through them is what keeps those surfaces from wearing down against each other.
Of these two jobs, petrol manages the first badly and the second never. A pump working on a petrol blend is wearing itself out, because petrol is thinner than diesel and strips out the lubrication the fuel system relies on. Petrol is also designed to resist igniting under compression — the reverse of what a diesel wants from its fuel — and that's where any rattling comes.
Taken together, they show what shape the issue takes. Contact doesn't do the damage — circulation does. Petrol in the tank is a fuel issue. After the pump has been running on that petrol, a mechanical fault has begun: anything shed by a pump that is grinding travels downstream to your injectors with your fuel.
Four situations our engineers see in White Cross: how bad is petrol in a diesel?
Filled up, and never started: nothing beats it. At a forecourt, and really only there, the petrol is still confined to the tank — because everywhere else the vehicle was driven to get to it. The task is emptying and cleaning on the spot.
Your ignition turned on, or a brief start. With the system primed, the fuel lines and filter now contain petrol that came from the tank. Normally nothing more than clearing, flushing and seeing to the fuel filter, so still easy.
Driven a couple of miles. Now the pump has spent these miles working on thinned fuel. The work is that tank, the lines, the fuel filter and fresh fuel through the entire system, and how hard the vehicle was driven counts as much as how far. Driving the children to Farrington Gurney Church of England Primary School is one sort of trip. A run as far as Wells, under 10 miles away, is a very different job. So is any mileage on the M32, under 15 miles from White Cross, where the engine has been running hard the whole time.
Driven on till it protested — clattering, smoke, a lumpy idle, a dead throttle. The fuel is not behaving like diesel any more, and your motor is saying so. Stop wherever you are — the verge on Bristol Road, a lay-by, a side street — and leave the car there. Lasting damage is very rare if a vehicle is pulled over quickly, and the fuel drain and flush that still come first sort it out.
White Cross drivers and that petrol in a diesel stories they hear
False: topping up to full with diesel makes it fine. It does not. A fuller tank of the same mix is all it gives, since topping up removes nothing. A diesel fuel system does not accept petrol by percentage in the way that guidance supposes.
Not so: a newer diesel copes with a bit of petrol. If anything, the opposite. More precise parts and higher pressure are how a modern diesel runs its fuel, and that makes the protection count more, not less.
This is the one that fools people. Myth: "If it starts and drives, there is no harm done." A petrol motor fed diesel normally will not run, and so the driver stops and the harm stops with them. Nothing seems to have happened when a diesel fed petrol fires up, ticks over and drives away, which it usually will; meanwhile the pump wears. Fine and running are not the same thing.
"A drop of two-stroke oil and drive it home" — a myth, borrowed from a fix from years ago, for a separate fault. The petrol is still inside the tank after that, and what it has diluted isn't put back.
Myth: "Drain the tank yourself and you are sorted." After the engine has been run, some of the petrol is no longer in the tank: it is in the filter and your lines, and it goes straight back through your pump on the next start. Also, a can of petrol drained at the roadside is truly risky.
Why petrol in a diesel takes place so easily
On purpose? Never. Through carelessness? Rarely, if ever. A diesel nozzle generally will not go into a petrol vehicle, but the smaller petrol nozzle goes into the filler of a diesel nearly without resistance — so forecourts make this one mistake straightforward, and only in that direction.
When routine and the vehicle stop matching, it happens. A new motor, a hire car or a courtesy car. One petrol and one diesel on the driveway of the same household. A forecourt you know, only with its pumps laid out differently. Fuelling up in a rush en route to Keynsham, with a train to catch. A new-to-you diesel Volkswagen Passat, its first fuelling, and a driver used to petrol: exactly when it takes place. Add a back seat full of children, a phone call or rain, and the hand wins.
White Cross people: how to prevent petrol in a diesel next time
- Check the petrol pump, not the colour. In the UK unleaded handles are generally green and diesel black, but not on every forecourt. The label is what counts.
- Many motors state the fuel inside the filler flap or on the cap, and so check it on your first fill in any vehicle you do not know.
- Good intentions do less than a sticker or a fob in a bright colour on your diesel's key when a house has one of each. So label it.
- Before the nozzle comes off the petrol pump the first time you fill a hired or new vehicle, say "diesel" out loud. Silly, perhaps, but it does the trick.
- Thinking about something else is when this becomes an easy mistake to make, and so tuck the phone away and keep your mind on the pump.
- Some diesels have a filler designed to block a petrol nozzle, and devices you can add exist for motors without one. Such an inhibitor helps up to a point — as a backstop, not a reason to stop checking the pump.
- Stop the moment you notice. Less petrol in that tank makes a weaker blend. It does not change what to do next, which is still not to crank it.
Put petrol in a diesel in White Cross already?
Then the order of things is short. Do not switch the ignition on, and don't fire it up. Yet on the forecourt, at Texaco or anywhere else? Ask the attendants to help you push the car away from 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 fault — White Cross has a page just for it.
White Cross petrol in a diesel tasks: why one costs more than another
Four different tasks lie behind the four situations above — which is why there's no fair single price. Which of them you're in is mostly what moves your cost. Where your car is matters too, and whether our van can safely get to it, after the proportion of petrol to what your tank holds.
Three queries come first, before any quote, rather than after — what went in, how much, has it run — and this is the reason. The answers turn a range into a straight figure.
About White Cross
White Cross is a small hamlet situated on the riverside in Somerset, with a relatively low elevation of 107 metres. White Cross lies near several other small settlements, including Hallatrow, Farrington Gurney, and Temple Cloud, and is approximately 8.5 miles from the city of Wells. White Cross has a population of around 528 people, predominantly living in detached houses. White Cross is also within commuting distance of larger cities, being around 104.6 miles from London.
Fuel drain cover in White Cross and across Somerset
White Cross waits in the BS postcode area, and our teams that answer petrol in diesel call-outs there work the spots around it as well — Hallatrow, Farrington Gurney and Temple Cloud among them. Our technicians drain where the vehicle is — your own driveway, a lay-by, a supermarket car park, a forecourt — so it does not have to come to us.
In White Cross and still at the petrol pump?
Then you are in the best position there can be. Keep the car switched off, then ring.