How Worried Should You Be? Petrol in a Diesel Car in Northfield
If it hasn't been started, worry far less than you likely are. "Have I wrecked it?" is the first question everyone around Northfield asks, and the honest answer is usually no, since petrol left in a diesel tank hurts nothing till it's dragged through your fuel system — by ignition priming, by your starter, or by being driven. Keep it that way: leave your motor off then 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 does not happen to you again.
Petrol in a diesel: what does it do to the motor?
Diesel does two jobs on its way through a motor. It protects first, and only then does it burn. Very fine tolerances go into the fuel injectors and the high-pressure pump, and only the diesel running through stops those surfaces grinding together.
Petrol handles the first job badly and the second not at all. A pump working on a petrol blend is wearing itself out, since petrol is thinner than diesel and strips out the lubrication the fuel system depends on. Petrol is also made to resist igniting under compression — the reverse of what a diesel needs from its fuel — and that's where the knocking comes.
Put these together and the shape of the trouble is plain. Not contact but movement is what causes the damage. Where the petrol is only inside the tank, it's a fault of fuel, nothing more. Once your pump has been labouring on that petrol, a mechanical issue has started: anything shed by a pump that's wearing down is carried downstream to the fuel injectors with the fuel.
Petrol in a diesel around Northfield: how bad is it? Four situations
The best case there can be: filled up, not once started. Being on a forecourt is what makes this possible: elsewhere, your car has been driven there to begin with. With that petrol kept in that tank alone, it's drained and purged right where it stands, and nothing more is needed.
The ignition switched on, or a short start. Petrol has come out of the tank and got to your filter and the fuel lines, because the fuel system has been primed. Drain, flush, deal with the fuel filter: still usually straightforward.
Your pump now spent a few miles on thinned fuel — that is what driving it does. How hard the car was driven matters as much as how far, and the work covers the tank, the lines, the filter and fresh fuel through the whole circuit. On the school run to St Mary's Church of England Primary School, the mileage is small. A run as far as Bath, under 10 miles away, is a very different task. So is any distance on the M32, under 15 miles from Northfield, where your engine has been labouring hard throughout.
Driven on until it complained — rattling, smoke, a ragged idle, a soft throttle. The fuel isn't behaving like diesel any more, and the engine is saying so. Pull up wherever you are — the verge on Hawthorn Road, a lay-by, a side street — and leave it there. Lasting damage is very rare when a car is pulled over soon, and the fuel drain and flush that still come first take care of it.
Stories Northfield drivers hear about petrol in a diesel
Myth: "Fill it the rest of the way with diesel and it'll be fine." It will not. Nothing is removed by topping up — you're left with a bigger tank, still the same mixture. That guidance supposes a diesel fuel system tolerates petrol by percentage. It does not.
Not so: a current diesel copes with a bit of petrol. Rather, the opposite. At higher pressure, through smaller components: that's how a newer diesel handles its fuel, so the protection matters more, not less.
Myth: "If it starts and drives, there is no harm done." This is the one that catches drivers. Any petrol engine fed diesel generally won't run, so the motorist stops and the harm stops with them. A diesel fed petrol usually starts, idles and drives away as if nothing has happened, while the pump wears. Running doesn't mean fine.
An outdated workaround for a distinct problem lies behind this one. Myth: "Add some two-stroke oil and drive the car home." It doesn't put back what petrol has thinned, and that petrol is still inside the tank later.
If your engine has been run, part of that petrol is in the filter and the fuel lines, not your tank — and your next start pulls it straight back through the pump. So the myth "drain the tank yourself and you are sorted" does not stand up. Emptying petrol into a can at the roadside is also genuinely risky.
How petrol ends up: petrol in a diesel
Carelessness is seldom the cause, and nobody means to do it. A diesel nozzle mostly will not fit a petrol car, but the smaller petrol nozzle goes into the filler of a diesel nearly without resistance — so forecourts make this one mistake straightforward, and just in one direction.
When routine and the car stop matching, it takes place. Hire cars, courtesy cars, and cars that are new to you. A household with one petrol and one diesel on the drive. Your usual forecourt, its pumps now in a different order. A hurried fill en route to Oldfield Park with a train to catch. Years of petrol vehicles behind you, a diesel Volkswagen Golf in front of you on the forecourt for its first tank — that is when. Your hand repeats what it has always done once you add rain, a phone call or a back seat full of children.
How to prevent petrol in a diesel at your next fill-up in Northfield
- The label is what matters, so read the petrol pump instead of the colour: in the UK unleaded handles are normally green and diesel black, yet not on each forecourt.
- In a motor you do not know, look inside the flap over the filler or at the cap before the first fill: many vehicles print the fuel type there.
- 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.
- 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 pump. It seems silly and it works.
- Put the phone away. This is an easy mistake to make whilst you are thinking about something else.
- Add-on devices are available for cars without one, and some diesels are built with a filler that will not accept a petrol nozzle. Useful — but a safety net only, never a reason to stop checking the label.
- As soon as you realise, stop: less petrol in your tank makes a thinner mix. What to do next does not change, though — still don't fire it up.
Already put petrol in a diesel around Northfield?
The order of things is short, then. Leave it unstarted, with your ignition off as well. If you are still on the forecourt — Shell or anywhere else — ask the attendants to help you push it away from the petrol pump. Call 0333 366 0103 next, with three facts — the fuel, the approximate quantity, and whether it's run.
Say so if it was AdBlue rather than petrol: it is a different problem, with its own page for Northfield, since AdBlue brings corrosion and deposits rather than lost protection.
One petrol in a diesel task in Northfield costs more than another. Why?
The four situations above are four separate tasks, so no single quote for this would be honest. Mostly, the cost shifts with which one you are in. Two things follow that: the petrol that went in as a proportion of what your tank takes, then the spot the car is in and whether our van can reach it safely.
What was put in, how much, and if it's run — three queries we ask before quoting, not after, for exactly that reason. Their replies are what turn a range into one firm number.
About Northfield
Northfield is a suburban area in Somerset, situated on the riverside at an elevation of 123 metres, with terraced housing being the predominant type of accommodation. Northfield lies approximately 7.2 miles from the city of Bath and is surrounded by nearby places such as Southfield, Writhlington, and Tyning. Northfield has a population of around 2814 residents and is located in the South West region of England, about 100.6 miles from London.
Fuel drain cover across Somerset, Northfield included
Our teams answering petrol in diesel calls in Northfield, in the BA postcode area, also work the spots near it, Southfield, Writhlington and Tyning included. No need to move the car to us. Forecourts, supermarket car parks, lay-bys and your own drive are all spots where we work.
Still at the petrol pump in Northfield?
No position is better: that is where you are. Keep it off. Ring.