How Worried Should You Be? Petrol in a Diesel Car in Spring Side
Provided it has not been started, you can worry far less than you probably are. Till the ignition primes your pump, your starter turns, or the car is driven, petrol in a diesel tank simply waits there and does no harm. Which means the truthful reply to that first Spring Side question — "have I ruined it?" — usually no. Petrol in Diesel is who to ring, with your engine kept off, so it remains that way. The rest 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 doesn't happen to you a second time.
Inside the engine: what petrol in a diesel does
On its way through a motor, diesel has two tasks. Lubricating comes before burning; it does both. The high-pressure pump and the fuel injectors are designed to very fine tolerances, and your diesel passing through them is what keeps those surfaces from wearing against one another.
Petrol handles the first job poorly and the second not at all. A pump working on a petrol mix is wearing itself out, because petrol is thinner than diesel and strips out the protection your fuel system depends on. Petrol is also designed to resist igniting under compression — the opposite of what a diesel needs from its fuel — and that is where any knocking starts.
Taken together, they make clear the shape the problem takes. It is movement that does the damage, not contact. Where the petrol is only inside your tank, it is an issue of fuel, nothing more. After your pump has been working on that petrol, a mechanical issue has begun: whatever is shed by a pump that's wearing down travels onward to the fuel injectors with the fuel.
Petrol in a diesel in Spring Side: how serious is it? Four situations
The best case there is: filled up, never started. On a forecourt, and genuinely only there, the petrol is still limited to your tank — because everywhere else the car was driven to reach it. The task is emptying and cleaning on the spot.
Your ignition turned on, or a brief start. The system has been primed, and so petrol has left that tank and got to your filter and your lines. That's usually still a simple job — a drain, a flush, and the fuel filter seen to.
The pump has spent a few miles on thinned fuel — that's what driving it does. Tank, lines, filter, then clean fuel run through the entire circuit: that is the work, and the way your car was driven matters as much as the distance. On the school run to Rawtenstall St Paul's Church of England Primary School, the miles is short. Very different once more: a trip to Salford, under 25 miles away, or some distance on the M66, under 3 miles from Spring Side, where the motor kept labouring hard.
Driven till it protested. Rattling, a ragged idle, smoke, a throttle that has gone soft. That is your motor telling you its fuel no longer is acting like diesel. Stop wherever you are — the verge on Greenbank Park, a lay-by, a side street — and leave the car there. A car stopped soon very seldom has long-term damage, because the fuel drain and the flush-through, which still come first, take care of it.
Spring Side drivers and the petrol in a diesel myths they hear
Myth: "Fill it the rest of the way with diesel and it'll be fine." It will not. Nothing comes out when you top up — that tank just holds more of the same mixture. The idea behind the guidance — that diesel fuel systems accept petrol by percentage — is wrong.
Myth: a newer diesel copes with a bit of petrol. Rather, the reverse. At higher pressure, through finer components: that is how a current diesel handles its fuel, and so the lubrication matters for more, not less.
This is the one that fools drivers. Myth: "If it starts and drives, there is no damage done." The driver of a petrol engine fed diesel normally stops, since it will not run, and the damage stops there. Nothing looks to have happened when a diesel fed petrol fires up, ticks over and drives away, as it usually will; meanwhile your pump grinds. Fine and running are not the same at all.
An outdated workaround for a separate issue is behind this one. Myth: "Add some two-stroke oil and drive the car home." The petrol is still inside that tank after that, and whatever it has weakened isn't put back.
The next start sends petrol back round your pump out of the fuel lines and your filter, where some of it sits after the motor has been run. That's why draining the tank yourself does not leave you sorted — a myth. Besides, petrol cleared into a can by the road is genuinely dangerous.
How does petrol in a diesel happen?
It's rarely carelessness, and no one does it on purpose. The petrol nozzle is the slimmer of the two and slides into a diesel filler with almost no resistance; a diesel nozzle generally will not go into a petrol motor at all. The forecourt makes it simple, and the mistake runs one way.
When routine and your car stop matching, it happens. Any car that is new to you — a hire car, on loan as a courtesy car, or just bought. A household with one petrol and one diesel on the driveway. Your ordinary forecourt, its pumps now in a different order. Filling up in a rush en route to Accrington, with a train to catch. A new-to-you diesel Renault Megane, its first fuelling, and a motorist used to petrol: precisely when it occurs. Add a back seat full of children, a phone call or rain, and habit takes over.
Spring Side motorists: how to prevent petrol in a diesel next time
- A green handle for unleaded and black for diesel is usual in the UK — but not on each forecourt. Trust the label on the petrol pump, not the colour.
- Inspect the filler flap. Many cars state the fuel inside the flap or on the cap. Look at it on your first fill in any motor you do not know.
- One of each in the home? Mark the key to the diesel — a coloured fob, a sticker — because meaning to remember isn't enough.
- "Diesel", out loud, before you pick up the nozzle — every time a new or hired car gets its first tank. It sounds silly. It works.
- Tuck the phone away. This is an easy mistake to make whilst you are thinking about something else.
- Up to a point, a misfuel inhibitor helps: some diesels have a filler designed to block a petrol nozzle, and add-on devices are available for the remainder. Count it as a safety net, then keep checking the petrol pump.
- Less petrol makes a weaker blend, and so stop as soon as you realise — though remembering that the next stage is unchanged. It is still not to crank it.
Already put petrol in a diesel around Spring Side?
Then the order of things is short. Do not turn your ignition on, and don't start it. If you're still at the forecourt — Tesco or anywhere else — ask the staff to help you push the car clear of the petrol pump. Next, 0333 366 0103. We'll ask what got in, roughly how much, and if it's been run.
AdBlue, not petrol? Then tell us. Corrosion and deposits, not lost lubrication, make it a different problem — Spring Side has a page all for it.
Spring Side petrol in a diesel tasks: why one costs more than another
There is no fair single price for this, because the four scenarios above are four different jobs. Which of them you are in is chiefly what shifts your cost. Where the vehicle is matters too, and whether a technician can safely get to it, after the ratio of petrol to what that tank takes.
What was put in, how much, and whether it's run — three queries our technicians ask before costing, not after, for exactly that reason. A range becomes a straight figure once the answers are in.
About Spring Side, for a moment
Spring Side is a suburban area in Lancashire, situated on the riverside with a mix of terraced housing. Spring Side has a population of around 3106 people and is located near other local places such as Rawtenstall, Higher Cloughfold, and Lower Cloughfold. Spring Side sits at an elevation of 201 metres, approximately 15.4 miles from Salford and 176.5 miles from London.
Across Lancashire and in Spring Side: fuel drain cover
Spring Side waits in the BB postcode area, and the vans that answer petrol in diesel call-outs there work the places near it as well — Rawtenstall, Higher Cloughfold and Lower Cloughfold among them. The vehicle does not need to come to us: our technicians drain at a forecourt, in a supermarket car park, in a lay-by or on your own drive.
Still at the petrol pump around Spring Side?
The best place there is, then — that's where you are. Keep it off. Phone.