Should You Worry? Petrol in a Diesel Car in Birkenside
Unstarted? Then less worried than you probably are. Everyone around Birkenside starts with "have I wrecked it?", and the honest answer is normally no: petrol resting in your tank of a diesel stays harmless till priming, cranking or driving pulls it into the fuel system. Leave your engine off and ring Petrol in Diesel — that keeps it that way. Read on for three things: the effect petrol has inside a diesel motor, the clues of how far it has spread, and ways to make sure you don't repeat it.
Your engine and petrol in a diesel: what goes on
On its way through a motor, diesel has two tasks. It protects first, and only then does it burn. Very fine gaps are built into your injectors and the high-pressure pump, and only the diesel flowing through stops those surfaces grinding together.
Petrol does the first job badly and the second not at all. Being less viscous than diesel, petrol strips away the protection a fuel system needs, leaving a pump running on that mixture wearing itself. It is also made to resist igniting under compression — the reverse of what a diesel needs — which is where you hear the knocking.
The shape of the problem is clear once you put those together. It is circulation that causes the damage, not contact. Petrol in a tank is a fuel issue. The beginning of a mechanical one is a pump that has been running 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 our technicians see in Birkenside
Fuelled but never started — as good as it gets. Being on a forecourt is what makes this the case: elsewhere, your car has been driven there to begin with. With that petrol held in that tank alone, it's emptied and cleaned on the spot, and nothing more is needed.
Started for a moment, or just your ignition on. Your system has been bled, and so petrol has left your tank and reached your filter and the lines. That's generally still a straightforward job — a drain, a flush, and your filter dealt with.
A few miles driven, and your pump has spent every one of them labouring on weakened fuel. How hard the vehicle was driven counts as much as how far, and the work covers your tank, your lines, the fuel filter and clean fuel through the entire system. On the school run to the local primary school, the distance is small. Very different again: a run to Edinburgh, under 10 miles away, or any miles on the M8, under 15 miles from Birkenside, where the motor never stopped labouring hard.
Clattering, a lumpy idle, smoke, a throttle gone soft: driven until it complained. The engine is telling you the fuel is no longer acting like diesel. Whether it's the verge on Birkenside, a lay-by or a side road, stop where you are then leave it. The drain and flush-through still come first, and they deal with it: if a vehicle is pulled over quickly, permanent damage is very uncommon.
Birkenside motorists and the petrol in a diesel myths they hear
Myth: "Fill it the rest of the way with diesel and it will be fine." It will not. Topping up removes nothing; it gives you a fuller tank of the same mix. A diesel fuel system does not accept petrol by percentage in the way that advice assumes.
Myth: "A newer diesel can cope with a bit of petrol." If anything, the reverse. Lubrication matters more on current diesels, not less, because their fuel runs through more precise components at higher pressure.
One myth that catches people out: if it starts and drives, it must be unharmed. Diesel in a petrol motor normally leaves a motor that won't run: the motorist stops, and so does the damage. While your pump wears, a diesel fed petrol normally starts, ticks over and drives away as though nothing has happened. Fine and running aren't the same thing.
An old fix for a different fault is behind this one. Myth: "Add some two-stroke oil and drive it home." What petrol has diluted stays weakened, and that petrol stays in your tank regardless.
Myth: "Drain the tank yourself and you are sorted." Once the engine has been run, some of the petrol is no longer in that tank: it is in your filter and the lines, and it goes right back through your pump on your next start. It is also really dangerous to drain petrol into a can by the roadside.
Why petrol in a diesel occurs so easily
It's rarely carelessness, and nobody does it on purpose. The forecourt makes it simple: the petrol nozzle is the smaller of the two, and it slides into a diesel filler with almost no resistance, whilst a diesel nozzle mostly will not go into a petrol vehicle at all. So the mistake runs one way.
It takes place when routine and your car stop matching. A vehicle that's new to you — hired, on loan as a courtesy car, or just bought. One petrol and one diesel on the driveway of the same household. A forecourt you know, but with its pumps arranged differently. A hurried fill en route to Gorebridge with a train to catch. The first fill-up in a diesel Volkswagen Passat after years of driving petrol is precisely the moment it occurs. The hand does what it has always done when you add rain, a phone call or a back seat full of kids.
Avoiding petrol in a diesel next time you fill up in Birkenside
- The label is what counts, and so read the petrol pump rather than the colour: in the UK unleaded handles are usually green and diesel black, but not on each forecourt.
- Check the filler flap. Plenty of vehicles state the fuel type inside the flap or on the cap. Look at it on your first fill in a car you don't know.
- A coloured fob or a sticker on your diesel's key achieves more than any amount of meaning to remember, in a house with one of each.
- It seems daft 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.
- Whilst you are thinking about something else, this is an easy mistake to make — so put the phone away.
- 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 pump.
- Stop as soon as you notice. Less petrol in the tank means a weaker mix. It doesn't change what to do next, which is still not to fire it up.
Petrol already in a diesel around Birkenside? Begin here
Then the order of things is brief. Leave it unstarted, with the ignition off as well. Ask the staff to help you push it away from the petrol pump if you are still on the forecourt, whether that is Shell or anywhere else. Next, 0333 366 0103. We'll ask what was put in, about how much, and if it's been run.
AdBlue, not petrol? Then say so. Corrosion and deposits, not lost lubrication, make it a separate issue — Birkenside has a page just for it.
One petrol in a diesel task in Birkenside costs more than another. Why?
A fair single price doesn't exist here: four scenarios, four separate jobs. The scenario itself does most of the work of moving the cost. The proportion counts next, meaning how much of the tank is petrol, and then the position of the vehicle and whether reaching it is safe for a technician.
What went in, how much, and whether it has run — three queries we ask before quoting, not after, for precisely that reason. The answers change a range into a straight figure.
About Birkenside and its setting
Birkenside is a suburban area situated on the riverside in Midlothian, with a mix of semi-detached housing and a population of around 2465 residents. Birkenside sits at an elevation of 143 metres, approximately 9.8 miles from Edinburgh, and is near other local communities such as Gorebridge and Arniston. Birkenside is part of the wider Edinburgh urban area, yet maintains its own distinct character. Birkenside residents are likely to commute to Edinburgh for work and other amenities.
Fuel drain cover in Birkenside and across Midlothian
Birkenside rests in the EH postcode area, and the teams that answer petrol in diesel calls there work the spots around it as well — Gorebridge, Arniston and North Middleton among them. The vehicle doesn't need to move to us: our engineers drain at a forecourt, in a supermarket car park, in a lay-by or on your own driveway.
Still at the pump in Birkenside?
Then, you could not be in a better spot. Keep it off. Ring.