How Worried Should You Be? Petrol in a Diesel Car in Altmore
If it has not been started, you can worry less than you probably are. Everyone in Altmore begins with "have I wrecked it?", and the fair answer is generally no: petrol left in the tank of any diesel remains harmless till priming, cranking or driving pulls it into the fuel system. Leave the engine off then call Petrol in Diesel — that is how you keep it like that. Further down, you will find what petrol actually does inside a diesel, how far it might have got, and how to stop it happening to you again.
Petrol in a diesel: what does it do to the engine?
Diesel does two tasks on its way through an engine. It protects first, and after that does it burn. Built to very fine gaps, the fuel injectors and your pump depend on the diesel moving through them to stop their surfaces wearing against one another.
The second job petrol doesn't do at all, and the first it does poorly. A pump working on a petrol mix is wearing itself out, since petrol is runnier than diesel and strips out the protection the fuel system depends 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 starts.
Together, those make the shape of the problem plain. It is circulation that causes the harm, not contact. All a tank with petrol in it amounts to is a fuel issue. Once your pump has been labouring on that petrol, a mechanical problem has begun: whatever is shed by a pump that is wearing is carried onward to the injectors with the fuel.
How bad is petrol in a diesel? Four situations we see in Altmore
Filled up, and never started: nothing beats it. Just that tank has petrol in it, and so the task is emptying your tank and flushing your system where your car sits. This situation can only really happen at a forecourt: anywhere else, your car got there by being driven.
Your ignition turned on, or a short start. With your system primed, your lines and filter already hold petrol that has come from that tank. Still usually easy: drain, flush, and the fuel filter dealt with.
Those few miles on the road were the pump running on fuel weakened by petrol the whole way. The work is that tank, the fuel lines, your filter and fresh fuel through the whole circuit, and how hard the car was driven matters as much as how far. The school run to the local primary school is one thing. Getting as far as Armagh, under 25 miles away, makes a very different job — as does any miles on the M77, over 50 miles from Altmore, with your engine running hard all the way.
Driven until it protested. Rattling, an uneven idle, smoke, a throttle that has gone soft. What you are hearing is the engine reporting fuel that no longer runs like diesel. Stop on the spot — on the verge on B842, at the kerb, down a side road — and don't move it again. What comes first is still the fuel drain and flush-through, and that sorts it out, with long-term damage very unusual if a vehicle is stopped early.
Altmore motorists and that petrol in a diesel myths they hear
"Top it up the rest of the way with diesel and it'll be fine" — a myth. It won't. Nothing is removed when you top up — your tank simply carries more of the same blend. The idea behind the guidance — that diesel fuel systems accept petrol by percentage — is wrong.
"Newer diesels can handle a little petrol" — a myth, and closer to the reverse. Finer parts and higher pressure are the way a newer diesel runs its fuel, and that makes the protection matter more, not less.
One myth that catches people out: if it starts and drives, it must be unharmed. Diesel in a petrol motor normally means a motor that won't run: the driver stops, and so does the harm. While your pump grinds, a diesel fed petrol usually starts, idles and drives away as if nothing has happened. Being able to run is not the same as being fine.
An outdated fix for a separate fault is behind this one. Myth: "Add some two-stroke oil and drive the vehicle home." None of what petrol weakened gets put back by it — and later, your tank still contains that petrol.
Myth: "Drain the tank yourself and you are sorted." After the engine has been run, some of that petrol is no longer in the tank: it's in the fuel filter and the fuel lines, and it goes right back through your pump at your next start. Clearing petrol into a can by the roadside is also genuinely hazardous.
How petrol ends up: petrol in a diesel
On purpose? Never. Through carelessness? Rarely, if ever. The petrol nozzle is the slimmer of the two and slips into a diesel filler with almost no resistance; a diesel nozzle generally will not go into a petrol vehicle at all. The forecourt makes it easy, and the slip runs one way.
It takes place when habit and your car stop matching. Hire cars, courtesy cars, and cars that are new to you. One petrol and one diesel on the driveway of the same household. A forecourt you know, only with its pumps arranged differently. A hurried fill on the way to the nearest station with a train to catch. Exactly the moment it occurs: after years of driving petrol, a driver fills a diesel Peugeot 308 for the first time. Add rain, a phone call or a back seat full of children, and your hand repeats what it has always done.
Altmore drivers: how to avoid petrol in a diesel next time
- The label is what counts, so read the pump instead of the colour: in the UK unleaded handles are usually green and diesel black, but not on every forecourt.
- Check your filler flap. Many cars state the fuel type inside the flap or on the cap. Look at it on the first fill in any car you don't know.
- One of each in the household? Mark the key to your diesel — a coloured fob, a sticker — since intending to remember is not enough.
- It sounds silly and it does the trick: on your first fill in a new or hired car, say "diesel" out loud before you lift the nozzle off the petrol pump.
- Mistakes like this are easy to make whilst your mind is on something else, and so your phone goes away.
- Up to a point, a misfuel inhibitor helps: some diesels have a filler built to refuse a petrol nozzle, and aftermarket devices exist for the rest. Treat it as a backstop, and keep checking the petrol pump.
- Less petrol makes a weaker mix, so stop as soon as you realise — while remembering that your next step is unchanged. It is still not to fire it up.
Petrol already in a diesel around Altmore? Begin here
Short and simple, then, is the order of things. Do not switch your ignition on, and do not start it. Ask the attendants to help you roll it clear of the pump if you're still on the forecourt, whether that's the nearest petrol station or somewhere else. Then call 0333 366 0103 and tell us what went in, roughly how much, and if it has run.
Say so if it was AdBlue instead of petrol: it is a separate fault, with its own page for Altmore, since AdBlue brings corrosion and deposits rather than lost protection.
Why one petrol in a diesel task in Altmore costs more than another
The four scenarios above are four separate tasks, so no single price for this would be honest. The scenario itself does most of the work of moving the cost. The proportion counts next, meaning how much of your tank is petrol, followed by the location of the car and whether reaching it is safe for a van.
What was put in, how much, and whether it has run — three questions we ask before costing, not after, for precisely that reason. The replies change a range into a straight figure.
About Altmore, for a moment
Altmore is a rural locality in County Tyrone, situated inland at an elevation of 225 metres. Altmore lies near the villages of Cappagh, Pomeroy, and Killay, and is approximately 19 miles from the city of Armagh. Altmore is characterised by its predominantly detached housing stock, reflecting its dispersed and rural nature. Altmore is also relatively distant from major urban centres, with London over 350 miles away.
Fuel drain cover in Altmore and across County Tyrone
Altmore rests in the BT postcode area, and the vans that answer petrol in diesel calls there work the locations near it as well — Cappagh, Pomeroy and Killay among them. The car does not need to come 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 petrol pump in Altmore?
Then you're in the best position there can be. Switched off it stays; then call.