How Worried Should You Be? Petrol in a Diesel Car in Bexley
If it hasn't been started, worry far less than you likely are. Everyone in Bexley begins with "have I ruined it?", and the fair answer is generally no: petrol resting in your tank of a diesel stays harmless till priming, cranking or driving draws it into the system. Leave the motor off and call Petrol in Diesel — that is how you keep it like that. The rest of this page sets out 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.
Petrol in a diesel: what does it do to the motor?
Passing through a motor, diesel does two jobs at once. Oiling comes before burning; it does both. What keeps the surfaces inside your high-pressure pump and your injectors from wearing against one another is the diesel flowing through them — they're built to extremely fine gaps.
Badly at the first, not at all at the second: that is petrol. A pump running on a petrol mixture is wearing itself out, since petrol is runnier than diesel and strips out the protection your 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's where the knocking comes.
The shape of the issue is plain when you put those together. Not contact but movement is what causes the harm. Where that petrol is only inside the tank, it is a problem of fuel, nothing more. A pump that has been running on that petrol is the beginning of a mechanical one, and whatever a worn pump sheds travels on with your fuel to the injectors downstream.
Petrol in a diesel in Bexley: how serious is it? Four situations
The best case there is: filled up, never started. Being on a forecourt is what makes this the case: elsewhere, your car has been driven there to begin with. With the petrol held in that tank alone, it's emptied and cleaned on the spot, and nothing more is needed.
Started for a second, or only the ignition on. With the system primed, the lines and filter now contain petrol that has come from your tank. Still normally easy: drain, flush, and the fuel filter dealt with.
Driven a few miles. Now your pump has spent these miles labouring on thinned fuel. Tank, lines, filter, then clean fuel run through the entire circuit: that's the work, and the way your car was driven matters as much as the miles. Short trips, like the school run to Old Bexley Church of England School, are one matter. Very different again: a run to London, under 15 miles away, or any distance on the M25, under 5 miles from Bexley, where the motor never stopped running hard.
It complained, and only then stopped: smoke, clattering, a throttle gone soft, an idle gone ragged. What you are hearing is the engine signalling fuel that no longer acts like diesel. Whether it's the verge on Bourne Road, a lay-by or a side street, stop there then leave it. A car stopped soon very seldom has lasting damage, as the fuel drain and the flush-through, which still go first, sort it out.
Myths Bexley people hear about petrol in a diesel
"Top it up the rest of the way with diesel and it will be fine" — a myth. It won't. Topping up removes nothing; it gives you a fuller tank of the same mixture. That advice presumes a diesel fuel system tolerates petrol by percentage. It does not.
If anything, the reverse is true. Myth: "A current diesel can cope with a bit of petrol." Protection matters more on modern diesels, not less, because their fuel passes through smaller parts at higher pressure.
Myth: "If it starts and drives, there is no damage done." This is the one that catches people. Feed diesel to a petrol motor and it generally will not run, so the motorist stops — and the harm stops with them. Nothing seems to have happened when a diesel fed petrol fires up, ticks over and drives away, which it usually will; meanwhile the pump grinds. Being able to run isn't proof of being fine.
"A drop of two-stroke oil and drive it home" — a myth, borrowed from a fix from years ago, for a different problem. What petrol has weakened remains thinned, and the petrol stays inside the tank regardless.
Myth: "Drain your tank yourself and you are sorted." After the motor has been run, some of the petrol is no longer in your tank: it is in the filter and the lines, and it goes right back through the pump at the next start. It's also genuinely risky to drain petrol into a can at the kerbside.
How petrol ends up: petrol in a diesel
On purpose? Never. Through carelessness? Seldom, if ever. The petrol nozzle is the smaller of the two and slips into a diesel filler with almost no resistance; a diesel nozzle mostly won't go into a petrol car at all. The forecourt makes it simple, and the mistake runs one way.
When routine and your car stop matching, it takes place. A vehicle that is new to you — a hire car, on loan as a courtesy car, or just bought. One petrol and one diesel on the drive of the same household. A forecourt you know, but with its pumps laid out differently. A rushed fill on the way to the nearest station with a train to catch. The first fill-up in a diesel Volkswagen Golf after years of driving petrol is exactly the moment it takes place. The hand repeats what it has always done when you add rain, a phone call or a back seat full of kids.
Next time you fill up in Bexley: preventing petrol in a diesel
- Check the petrol pump, not the colour. In the UK unleaded handles are normally green and diesel black, yet not on every forecourt. The label is what matters.
- Many motors state the fuel type inside the filler flap or on the cap, so check there on your first fill in a car you don't know.
- Good intentions count for less than a sticker or a fob in a vivid colour on the diesel's key if a house has one of each. So mark it.
- "Diesel", aloud, before you pick up the nozzle — every time a new or hired car needs its first tank. It seems silly. It works.
- Thinking about something else is when this becomes an easy mistake to make, so put your phone away then keep your mind on the petrol pump.
- Up to a point, a misfuel inhibitor helps: some diesels have a filler designed to refuse a petrol nozzle, and add-on devices exist for the rest. Count it as a backstop, and keep checking the pump.
- As soon as you realise, stop: less petrol inside the tank makes a thinner mixture. What to do next doesn't change, though — still do not start it.
Bexley: already put petrol in a diesel?
Short and simple, then, is the order of things. Never start it, and do not switch your ignition on. Yet at the forecourt, at the nearest petrol station or anywhere else? Ask the attendants to help you push the vehicle away from the petrol pump. Next, 0333 366 0103. We will ask what was put in, roughly how much, and if it has been run.
AdBlue, not petrol? Then say so. Corrosion and deposits, not lost protection, make it a different issue — Bexley has a page just for it.
One petrol in a diesel job in Bexley costs more than another. Why?
The four situations above are four separate jobs, so no single quote for this would be honest. Which of them you are in is chiefly what shifts your cost. The share counts next, meaning how much of your tank is petrol, and then the position of the vehicle and whether getting to it is safe for our van.
Three queries come first, before any quote, instead of after — what was put in, how much, has it run — and that is the reason. Those answers are what turn a range into one firm number.
About Bexley, for a moment
Bexley is a locality in the London Borough of Bexley, situated on the banks of the River Cray in southeast London. Bexley sits at a low elevation of around 13 metres above sea level, with semi-detached housing being the predominant type of accommodation. Bexley is located near other local places such as Old Bexley, Coldblow, and North Cray, and is approximately 12 miles from central London.
Across Greater London and around Bexley: fuel drain cover
Our teams answering petrol in diesel call-outs in Bexley, in the DA postcode area, also work the places around it, Old Bexley, Coldblow and North Cray among them. You need not bring your car to us. Forecourts, supermarket car parks, lay-bys and your own drive are all spots where we work.
In Bexley and still at the pump?
Then, you could not be in a better position. Turned off it remains; then call.