Petrol in a Diesel Car in Central: How Worried Should You Be?
Likely less than you are now — provided no one has started the car. Petrol sitting in a diesel tank does nothing to your motor till something pulls it through your fuel system — the ignition priming the pump, the starter, or driving on its own. So the truthful answer to the first question everyone around Central asks, "have I wrecked it?", is normally no. Leave the motor off then ring Petrol in Diesel — that keeps it like that. The remainder of this page explains 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 again.
What petrol in a diesel does to the engine
Passing through an engine, diesel does two things at the same time. Lubricating comes before burning; it does both. Very fine gaps go into the fuel injectors and your high-pressure pump, and only your diesel running through keeps those surfaces from grinding together.
Of these two tasks, petrol handles the first poorly and the second not at all. Being less viscous than diesel, petrol strips away the lubrication a fuel system needs, leaving a pump on the blend wearing itself. It is also made to resist igniting under compression — the reverse of what a diesel needs — which is where you hear the clattering.
The shape of the issue is plain once you put those together. Not contact but circulation is what does the harm. A tank with petrol in it is a fuel problem. A pump that has been working on that petrol is the beginning of a mechanical one, and whatever a worn pump sheds travels on with your fuel to the injectors further on.
How bad is petrol in a diesel? Four scenarios we see in Central
Filled but never started — as good as it gets. The petrol is inside your tank and just the tank, and the job is a drain and a flush where the car stands. This is the one situation that can only really happen at a forecourt, as anywhere else the car has been driven to get there.
A brief spell of running, or just your ignition on. The system has been bled, and so petrol has left the tank and reached the filter and the lines. That's usually still a straightforward job — a drain, a flush, and the fuel filter seen to.
Driven a few miles. Now the pump has spent these miles labouring on weakened fuel. The work is that tank, your lines, the fuel filter and fresh fuel through the whole circuit, and how hard the vehicle was driven matters as much as how far. On the school run to the local primary school, the miles is small. A run as far as Glasgow, under 25 miles away, is a very different job. So is any miles on the M8, under 10 miles from Central, where your engine has been labouring hard the whole time.
Driven until it complained. Clattering, an uneven idle, smoke, a throttle that has gone soft. The fuel is not acting like diesel any more, and the engine is telling you. Pull up where you are — on the verge on Murdieston Street, at the kerb, down a side road — and don't move it again. A car stopped soon very seldom has long-term damage, as the fuel drain and the flush-through, which still go first, sort it out.
What Central drivers get told about petrol in a diesel — and the myths in it
False: topping up to full with diesel makes it fine. It doesn't. Nothing comes out when you top up — the tank simply carries more of the same mixture. The assumption behind the advice — that diesel fuel systems tolerate petrol by percentage — is wrong.
Not so: a current diesel copes with a bit of petrol. Rather, the reverse. Lubrication matters more on current diesels, not less, since their fuel passes through smaller components at higher pressure.
"It starts, it drives, and so there is no harm" — the myth that catches most motorists than any other. A petrol motor fed diesel usually won't run, 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, as it usually does; meanwhile the pump grinds. Running does not mean fine.
"A drop of two-stroke oil and drive it home" — a myth, borrowed from a fix from years ago, for a distinct problem. What petrol has diluted stays weakened, and that petrol remains inside your tank regardless.
Myth: "Drain that tank yourself and you are sorted." Once the engine has run, some of the petrol is no longer inside the tank: it's in the fuel filter and the fuel lines, and it goes right back through your pump on your next start. It's also genuinely dangerous to drain petrol into a can at the kerbside.
Petrol in a diesel: how does it take place?
A careless moment is seldom the cause, and nobody means to do it. One way only, because of the nozzles: the smaller petrol one slips inside a diesel filler with almost no resistance, while the diesel one generally won't fit a petrol vehicle. That is how the forecourt makes it simple.
Routine and the vehicle getting out of step is when it takes place. A new motor, a hire car or a courtesy car. Households running one of each, petrol and diesel. A familiar forecourt with the pumps in a different order. Racing for a train at Greenock West and filling up en route. A new-to-you diesel Volkswagen Tiguan, its first fuelling, and a motorist used to petrol: precisely when it takes place. Add rain, a phone call or a back seat full of kids, and your hand does what it has always done.
How to avoid petrol in a diesel at your next fill-up in Central
- Read the petrol pump, not the colour. In the UK unleaded handles are usually green and diesel black, yet not on every forecourt. The label is what matters.
- In a motor you do not know, look inside the flap over your filler or at the cap before the first fill: many motors state the fuel there.
- Label the key. In a house with one of each, a coloured fob or a sticker on your diesel's key does more than any amount of meaning to remember.
- "Diesel", out loud, before you pick up the nozzle — every time a new or hired car needs its first tank. It sounds silly. It does the trick.
- Thinking about something else is when this becomes an easy mistake to make, so put the phone away then keep your mind on the pump.
- Add-on devices exist for vehicles without one, and some diesels come with a filler that will not accept a petrol nozzle. Useful — but a backstop at best, never a reason to stop checking the label.
- Less petrol means a weaker blend, and so stop as soon as you realise — though remembering that the next stage is unchanged. It's still not to fire it up.
Already put petrol in a diesel around Central?
The order of things is short, then. Leave it unstarted, with your ignition off too. Yet at the forecourt, at Tesco or anywhere else? Ask the staff to help you push the car clear of the petrol pump. Phone 0333 366 0103 next, with three answers — the fuel, the rough amount, and if it's run.
If it was AdBlue instead of petrol, say so. That's a separate issue — corrosion and deposits and not lost protection — and it has its own page for Central.
Central petrol in a diesel tasks: why one costs more than another
The four scenarios above are four different tasks, so no single price for this would be fair. Mostly, your cost moves with which situation you're in. After that it is the ratio — how much petrol got in against how much your tank takes — and then where your car is and whether a technician can get to it safely.
Three questions come first, before quoting, instead of after — what went in, how much, has it run — and this is the reason. Those replies are what turn a range into one firm number.
About Central, for a moment
Central is a coastal suburban area in Inverclyde, situated near the cities of Glasgow and Greenock. Central sits at an elevation of 48 metres, with its predominant housing being flats, and is home to a population of approximately 7756 residents. Central is located near other suburban areas such as Cornhaddock, Cowdenknowes, and Overton, and is within commuting distance to Glasgow, which is 21.5 miles away.
Fuel drain cover around Central and across Inverclyde
Petrol in diesel calls in Central — part of the PA postcode area — go to teams that likewise cover the places round it, Cornhaddock, Cowdenknowes and Overton among them. The vehicle doesn't need to come to us: our technicians drain on a forecourt, in a supermarket car park, in a lay-by or on your own driveway.
In Central and still at the pump?
Then you are in the best place there can be. Leave the vehicle turned off, and ring.