Birks: Petrol in a Diesel Car? How Worried to Be
Less than you likely are, if it has not been started. Till the ignition primes the pump, the starter turns, or the vehicle is driven, petrol in a diesel tank simply sits there and does no harm. Which makes the truthful reply to that first Birks question — "have I wrecked it?" — normally no. Leave your engine off and ring Petrol in Diesel — that is how you keep it like that. What petrol really does to a diesel, how to judge how far it has gone, and how to stop it from happening a second time: that is the remainder of this page.
What petrol in a diesel does to the motor
On its way through an engine, diesel has two tasks. Before it ignites, it protects — then it combusts. Made to very fine gaps, your injectors and the pump depend on your diesel flowing through them to keep their surfaces from wearing against one another.
The second job petrol doesn't do at all, and the first it does badly. A pump running on a petrol mixture is wearing itself out, because petrol is runnier than diesel and strips out the protection the fuel system relies on. Petrol is also designed to resist igniting under compression — the reverse of what a diesel needs from its fuel — and that is where the clattering comes.
The shape of the trouble is plain when you put those together. Contact doesn't do the damage — circulation does. Petrol in the tank is a fuel issue. A pump that has been running on that petrol is the beginning of a mechanical one, and whatever a worn pump sheds moves on with the fuel to the fuel injectors downstream.
Petrol in a diesel around Birks: how bad is it? Four situations
Filled but not once started — as good as it gets. Just your tank has petrol in it, so the task is draining that tank and purging the fuel system where the car stands. This scenario can only truly take place at a forecourt: anywhere else, the car got there by being driven.
Started for a moment, or just your ignition on. With your system primed, the lines and filter now hold petrol that came from the tank. Still normally simple: drain, flush, and the filter dealt with.
The pump now worked a few miles on thinned fuel — that's what driving the car meant. The work is the tank, the lines, the filter and clean fuel through the entire circuit, and how hard the car was driven counts as much as how far. Driving the children to Fountain Primary School is one sort of trip. Very different a second time: a trip to Leeds, under 5 miles away, or some mileage on the M62, under a mile from Birks, where your engine kept labouring hard.
Driven until it protested. Knocking, an uneven idle, smoke, a throttle that has gone soft. The fuel isn't behaving like diesel any more, and your engine is telling you. Stop wherever you are — the verge on Denton Terrace, a lay-by, a side street — and leave the vehicle there. A car stopped soon very rarely has long-term damage, as the fuel drain and the flush-through, which still come first, sort it out.
Stories Birks drivers hear about petrol in a diesel
It will not be fine. The myth: "Fill it the rest of the way with diesel and it will be." A fuller tank of the same mix is all it gives, since topping up takes out nothing. Percentage isn't how a diesel fuel system tolerates petrol, whatever that advice presumes.
Myth: "A modern diesel can cope with a bit of petrol." If anything, the reverse. A modern diesel sends its fuel through more precise parts at higher pressure, which makes the protection count more, not less.
Myth: "If it starts and drives, there's no damage done." This is the one that catches people. Any petrol engine fed diesel normally won't run, and so the driver stops and the damage stops with them. A diesel fed petrol normally starts, idles and drives away as though nothing has happened, while your pump grinds. Fine and running are not the same thing.
Myth: a two-stroke additive lets you to drive home. It is an old fix, supposed for another issue. That petrol is still in the tank after that, and what it has thinned isn't put back.
Once the motor has run, part of that petrol is in the fuel filter and the fuel lines, not your tank — and your next start pulls it right back through the pump. So the myth "drain that tank yourself and you're sorted" doesn't stand up. And, a can of petrol filled at the roadside is genuinely risky.
Why petrol in a diesel occurs at all
It is seldom carelessness, and no one does it on purpose. The petrol nozzle is the narrower of the two and slips into a diesel filler with almost no resistance; a diesel nozzle mostly will not go into a petrol motor at all. The forecourt makes it simple, and the error runs one way.
It occurs when habit and the car stop matching. A car that is new to you — hired, on loan as a courtesy car, or just bought. A household with one petrol and one diesel on the drive. A forecourt you know, only with its pumps arranged differently. A hurried fill en route to Morley with a train to catch. Years of petrol motors behind you, a diesel Volkswagen Passat 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 simply does what it always has.
Birks motorists: how to prevent petrol in a diesel next time
- Check the pump, not the colour. In the UK unleaded handles are normally green and diesel black, but not on every forecourt. The label is what counts.
- Many cars state the fuel inside the filler flap or on the cap, and so check it on your first fill in a motor you don't know.
- Good intentions count for less than a sticker or a fob in a vivid colour on the diesel's key when a home has one of each. So mark it.
- Say it before you lift it. On the first fill in a new or hired car, say "diesel" out loud before you lift the nozzle off the petrol pump. It seems daft and it does the trick.
- Tuck the phone away. This is an easy mistake to make while you are thinking about something else.
- Add-on devices exist for cars without one, and some diesels are built with a filler that will not take a petrol nozzle. Helpful — but a safety net only, never a reason to stop checking the label.
- Noticing it mid-fill? Stop at once. A weaker mixture follows from less petrol in that tank, yet your next stage stays the same: do not crank it.
Petrol already in a diesel in Birks? Start here
Then, there is only a short order of things. Starting it is out, and so is turning on your ignition. If you're still at the forecourt — Asda or anywhere else — ask the attendants to help you roll it away from the pump. Phone 0333 366 0103 next, with three facts — the fuel, the approximate volume, and whether it has run.
Corrosion and deposits are the issue with AdBlue, whereas petrol means lost protection. So if it was AdBlue, say so — and see its own Birks page.
One petrol in a diesel job around Birks costs more than another. Why?
An honest single price does not exist here: four scenarios, four separate tasks. Chiefly, the cost shifts with which situation you're in. Beyond that it's the share — how much petrol went in against how much that tank takes — and then where the car is and whether our van can reach it safely.
That's why our technicians ask three queries before costing instead of after: what went in, how much, and if it has run. With those answers, you get a straight figure instead of a range.
About Birks itself
Birks is a suburban area situated on the riverside in West Yorkshire, with an elevation of 158 metres and a mix of terraced housing. Birks lies approximately 4.8 miles from Leeds, making it a commuter-friendly location. Birks is surrounded by nearby places such as America Moor, Topcliffe, and Town End, and is home to around 7017 residents. Birks benefits from its proximity to Leeds, while maintaining a distinct local character.
Fuel drain cover across West Yorkshire, Birks included
America Moor, Topcliffe and Town End are among the spots around Birks that the same vans work, answering petrol in diesel call-outs across Birks's LS postcode area. You need not bring the vehicle to us. Forecourts, supermarket car parks, lay-bys and your own driveway are all locations where we work.
At the pump in Birks, still?
Then, you couldn't be in a better place. Keep it off. Call.