Petrol in a Diesel Car in North Corner: How Worried Should You Be?
Far less than you likely are, if it hasn't been started. "Have I ruined it?" is the first question everyone in North Corner asks, and the honest answer is normally no, because petrol left in a diesel tank hurts nothing till it is dragged through the fuel system — by ignition priming, by your starter, or by driving. Keep it like that: leave your engine off and call Petrol in Diesel. Read on for three things: the effect petrol has inside a diesel motor, the signs of how far it has spread, and the way to make sure you never do it again.
Petrol in a diesel: what does it do to your engine?
Passing through an engine, diesel is doing two jobs at the same time. Before it ignites, it lubricates — and then it ignites. Very fine tolerances go into the injectors and the high-pressure fuel pump, and only the diesel flowing through stops their surfaces grinding together.
The second task petrol doesn't do at all, and the first it does poorly. Being less viscous than diesel, petrol strips out the lubrication a fuel system needs, leaving a pump on the blend wearing itself. It is also made to resist igniting under compression — the opposite of what a diesel needs — which is where you hear the rattling.
Put these together and the shape of the trouble is clear. Contact does not do the harm — circulation does. Petrol in the tank is a fuel fault. The start 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 downstream.
Petrol in a diesel in North Corner: how serious is it? Four situations
Fuelled up, not once started. The best case there is. Just your tank has petrol in it, so the job is draining the tank and rinsing the fuel system where the vehicle sits. This scenario can only truly happen on a forecourt: anywhere else, your car got there by being driven.
Ignition on, or started for a moment. Once primed, the fuel system has drawn petrol from the tank as far as the fuel filter and the fuel lines. Drain, flush, see to your filter: still usually simple.
Those few miles driven meant the pump working on fuel weakened by petrol throughout. The work is the tank, the fuel lines, the fuel filter and clean fuel through the entire circuit, and how hard your car was driven counts as much as how far. On the school run to Frampton Cotterell Church of England Primary School, the distance is small. A run as far as Bristol, under 10 miles away, is a very different task. So is any distance on the M4, under 3 miles from North Corner, where your engine has been running hard throughout.
Clattering, an uneven idle, smoke, a throttle gone soft: driven until it complained. The engine is telling you your fuel is no longer acting like diesel. Stop where you are — on the verge on Church Road, at the kerb, down a side road — and do not move it. Long-term damage is very rare if a car is stopped soon, and the fuel drain and flush that still go first sort it out.
Petrol in a diesel myths North Corner people hear
"Top it up the rest of the way with diesel and it'll be fine" — a myth. It won't. Topping up takes out nothing; it gives you a bigger tank of the same mix. That guidance supposes a diesel fuel system tolerates petrol by percentage. It doesn't.
If anything, the reverse is true. Myth: "A current diesel can cope with a bit of petrol." At higher pressure, through smaller components: that's how a current diesel handles its fuel, and so the protection counts for more, not less.
"It starts, it drives, so no harm done" — the myth that catches more drivers than any other. The motorist of a petrol motor fed diesel normally has no choice but to stop, since it will not run, and the harm stops there. While your pump wears, a diesel fed petrol usually starts, idles and drives away as if nothing has happened. Being able to run isn't the same as being fine.
An old workaround for a separate problem is behind this one. Myth: "Add some two-stroke oil and drive the vehicle home." The petrol is still in that tank after that, and what it has thinned is not put back.
"Drain it yourself and you're sorted" — a myth, since after it's been running some petrol sits in the fuel filter and lines, waiting to go right back through the pump on your next start. On top of that, petrol emptied into a can by the road is genuinely hazardous.
How it happens: petrol in a diesel
Nobody does it on purpose, and it's rarely carelessness. A diesel nozzle generally won't fit a petrol motor, yet the smaller petrol nozzle goes into the filler of a diesel nearly without resistance — so forecourts make this one error straightforward, and only in that direction.
The moment habit stops matching the vehicle is the moment it happens. Any car that's new to you — hired, on loan as a courtesy car, or brand new. A household with one petrol and one diesel on the drive. A familiar forecourt with the pumps in a different order. A train to catch, and a rushed fill en route to Bristol Parkway. Years of petrol motors behind you, a diesel Volkswagen Golf in front of you at the forecourt for its first tank — that is when. Throw in rain, a phone call or a back seat full of kids, and the hand repeats what it has always done.
Avoiding petrol in a diesel next time you fill up in North Corner
- Not every forecourt in the UK keeps to green for unleaded and black for diesel, even if most generally do. Check the petrol pump's label; the colour is only a clue.
- Many cars state the fuel type inside the filler flap or on the cap, so check there on the first fill in any motor you don't know.
- Good intentions count for less than a sticker or a fob in a bright colour on your diesel's key if a household has one of each. So label it.
- "Diesel", aloud, before you pick up the nozzle — every time a new or hired car gets its first tank. It sounds daft. It does the trick.
- Thinking about something else is when this becomes an easy mistake to make, and so tuck your phone away then keep your mind on the pump.
- Some diesels come with a filler built to refuse 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 checking the petrol pump.
- The moment you notice, stop: less petrol inside that tank makes a thinner mixture. What to do next doesn't change, though — still don't start it.
Already put petrol in a diesel in North Corner?
Short and simple, then, is the order of things. Don't start it, and don't turn your ignition on. Still on the forecourt, at BP or anywhere else? Ask the attendants to help you roll it clear of the pump. What was put in, about how much, and if it's run: tell us those when you phone 0333 366 0103.
If it was AdBlue and not petrol, say so. That is a different problem — corrosion and deposits and not lost protection — and it has its own page for North Corner.
North Corner petrol in a diesel tasks: why one costs more than another
The four situations above are four different tasks, so no single price for this would be fair. What shifts the cost is mostly which of them you are in. Where your car is matters too, and whether our van can safely get to it, after the share of petrol to what that tank holds.
That's why our technicians ask three queries before quoting instead of after: what got in, how much, and if it's run. Given the replies, you get a straight figure rather than a range.
About North Corner and its setting
North Corner is a suburban area in Gloucestershire, situated inland at an elevation of 54 metres, approximately 7.5 miles from Bristol. North Corner is characterized by its predominantly detached housing stock, reflecting the area's residential development. North Corner sits near several nearby places, including Frampton Cotterell, Watleys End, and Frampton End, and is home to around 1096 residents.
Across Gloucestershire and around North Corner: fuel drain cover
The teams answering petrol in diesel jobs around North Corner, in the BS postcode area, equally work the locations around it, Frampton Cotterell, Watleys End and Frampton End among them. No need to move the vehicle to us. Forecourts, supermarket car parks, lay-bys and your own driveway are all spots we drain.
At the pump in North Corner, right now?
No position is better: that's where you now are. Ring, and keep it switched off.