How Worried Should You Be? Petrol in a Diesel Car in Parr
Provided it hasn't been started, you can worry far less than you probably are. Until the ignition primes your pump, the starter turns, or your vehicle is driven, petrol in a diesel tank just rests there and does nothing. Which means the truthful reply to that first Parr question — "have I ruined it?" — usually no. Keep it that way: leave the engine off and phone Petrol in Diesel. The rest of this page explains what petrol really does to a diesel, how to judge how far it has got, and how to make sure it doesn't happen to you again.
Inside the engine: what petrol in a diesel does
Two jobs fall to diesel on its route round a motor. It ignites, and before it ignites it lubricates. Designed to very fine gaps, the fuel injectors and your pump depend on the diesel flowing through them to keep their surfaces from wearing against one another.
Of these two jobs, petrol handles the first poorly and the second not at all. A pump working on a petrol mixture is wearing itself out, since petrol is runnier than diesel and takes away the protection the 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's where the knocking starts.
The shape of the trouble is clear once you put those together. Contact does not do the harm — movement does. Any tank with petrol in it is a fuel fault. The start of a mechanical one is a pump that has been labouring on that petrol — and whatever a worn pump sheds moves on with the fuel to the fuel injectors beyond it.
How serious is petrol in a diesel? Four situations we see around Parr
Fuelled but never started — as good as it gets. At a forecourt, and truly only there, the petrol is still limited to the tank — since everywhere else your car was driven to get to it. The job is emptying and flushing on the spot.
Your ignition switched on, or a brief start. With the system primed, your lines and filter already contain petrol that has come from that tank. That is normally still an easy task — a drain, a flush, and your filter seen to.
Those few miles driven meant the pump labouring on fuel weakened by petrol throughout. Distance is only half of it; how hard it was driven counts equally. Either way the work includes that tank, the lines, the filter and fresh fuel through the whole system. A school run to Broad Oak Community Primary School is one thing. Very different once more: a trip to Liverpool, under 15 miles away, or any distance on the M62, under 3 miles from Parr, where the motor never stopped labouring hard.
Driven on until it complained — rattling, smoke, a ragged idle, a soft throttle. The engine is telling you your fuel is no longer acting like diesel. Whether it is the verge on Ashtons Green Drive, a lay-by or a side road, stop where you are then leave it. The fuel drain and flush still go first, and they deal with it: when a car is pulled over early, long-term damage is very uncommon.
Petrol in a diesel stories Parr people hear
It will not be fine. The myth: "Fill it the rest of the way with diesel and it'll be." A bigger tank of the same mixture is all you get, because topping up takes out nothing. A diesel fuel system does not accept petrol by percentage in the way that guidance presumes.
"Current diesels can handle a little petrol" — a myth, and closer to the reverse. Protection counts more on newer diesels, not less, because their fuel runs through smaller parts at higher pressure.
Myth: "If it starts and drives, there is no damage done." This is the one that catches drivers. The motorist of a petrol motor fed diesel normally stops, because it will not run, and the harm stops with them. While your pump grinds, a diesel fed petrol usually starts, ticks over and drives away as though nothing has happened. Fine and running are not 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." What petrol has thinned remains weakened, and the petrol stays in the tank anyway.
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 right back through your pump at your next start. Besides, petrol cleared into a can by the road is truly risky.
Petrol in a diesel: how does it happen?
No one does it on purpose, and it is seldom carelessness. One way only, because of the nozzles: the narrower petrol one slips inside a diesel filler with almost no resistance, whereas the diesel one mostly will not fit a petrol car. That's how the forecourt makes it simple.
When habit and the car stop matching, it happens. Courtesy car, hire car, or a vehicle that is new. Households running one of each, petrol and diesel. A forecourt you know, but with its pumps laid out differently. Filling up in a hurry en route to St Helens Junction, with a train to catch. Years of petrol motors behind you, a diesel Renault Megane in front of you on the forecourt for its first tank — that is when. With rain, a call arriving, or a car full of children to deal with, your hand just does what it has always done.
How to avoid petrol in a diesel at your next fill-up around Parr
- Not every forecourt in the UK follows green for unleaded and black for diesel, though most generally do. Check the pump's label; the colour is only a clue.
- The first fill in a new vehicle is the time to check the filler flap — on it, or on the cap, many cars state the fuel to use.
- A coloured fob or a sticker on your diesel's key does more than any amount of meaning to remember, in a home with one of each.
- It seems silly and it works: on your first fill in a new or hired car, say "diesel" out loud before you lift the nozzle off the petrol pump.
- Put the phone away. This is an easy mistake to make while you are thinking about something else.
- Up to a point, a misfuel inhibitor helps: some diesels come with a filler built to reject a petrol nozzle, and aftermarket devices are available for the remainder. Treat it as a safety net, and keep reading the petrol pump.
- Stop as soon as you notice. Less petrol in your tank makes a thinner blend. It doesn't change what to do next, which is still not to crank it.
Petrol already in a diesel around Parr? Begin here
Then, there's only a short order of things. Starting it is out, and so is switching on the ignition. Ask the staff to help you roll it clear of the petrol pump if you're still at the forecourt, whether that is Horseshoe Garage or somewhere else. Next, 0333 366 0103. We'll ask what was put in, about how much, and if it has been run.
Corrosion and deposits form the problem with AdBlue, whereas petrol brings lost protection. So if it was AdBlue, say so — and see its own Parr page.
Parr petrol in a diesel jobs: why one costs more than another
The four scenarios above are four different jobs, so no single price for this would be honest. Chiefly, your cost moves with which one you're in. Next it's the share — how much petrol went in against how much your tank takes — and then where the car is and whether a van can get to it safely.
What went in, how much, and whether it has run — three questions our engineers ask before pricing, not after, for precisely that reason. Their answers are what turn a range into one firm number.
About Parr, for a moment
Parr is a suburban area in Merseyside, situated on the riverside with an elevation of 29 metres, and is located near the cities of Liverpool and other nearby places such as Moss Nook and Ashtons Green. Parr has a population of approximately 4968 residents and predominantly features terraced housing. Parr is positioned within the North West region of England, around 11.8 miles from Liverpool and 172.3 miles from London.
Parr and Merseyside: where our fuel drain cover reaches
Parr sits in the WA postcode area, and the teams that answer petrol in diesel calls there work the spots around it as well — Moss Nook, Ashtons Green and Derbyshire Hill among them. A forecourt, a supermarket car park, a lay-by or your own drive are all places our engineers work, and your vehicle doesn't need to come to us.
Still at the pump in Parr?
No position is better: that's where you now are. Keep it off. Ring.