How Worried Should You Be? Petrol in a Diesel Car in Digmoor
Probably less than you are now — provided no one has started the vehicle. Until your ignition primes your pump, your starter turns, or your vehicle is driven, petrol in a diesel tank simply waits there and does nothing. Which means the honest reply to the first Digmoor query — "have I ruined it?" — usually no. Petrol in Diesel is who to ring, with the motor left off, so it remains that way. Read on for three things: the effect petrol has inside a diesel motor, the clues of how far it has spread, and the way to make sure you never repeat it.
What petrol in a diesel does to the engine
Two jobs fall to diesel on its journey through a motor. It combusts, and before it burns it protects. The high-pressure fuel pump and the injectors are built to very fine tolerances, and your diesel passing through them is what stops those surfaces from wearing down against one another.
Of those two jobs, petrol handles the first badly and the second never. It's thinner than diesel and takes away the protection your fuel system rests on, so a pump running on a petrol blend is a pump wearing itself. And petrol is made to resist igniting under compression, which is the reverse of what a diesel needs from its fuel. That's where the clattering comes from.
Combined, those make the shape of the problem clear. The harm is done by circulation, not by contact. Petrol in the tank 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 moves on with the fuel to the injectors downstream.
Digmoor, petrol in a diesel: four cases, from mild to serious
Fuelled, and not started: no case is better. On a forecourt, and genuinely only there, the petrol is still limited to the tank — since anywhere else the car was driven to get to it. The task is emptying and purging on the spot.
The ignition switched on, or a short start. Once primed, the system has pulled petrol out of your tank up to the filter and the lines. Still usually easy: drain, flush, and the filter sorted.
Those few miles driven meant your pump running on fuel diluted by petrol throughout. The work is the tank, the lines, your filter and fresh fuel through the entire system, and how hard the car was driven counts as much as how far. The school run to St Francis of Assisi Catholic Primary School is one matter. A run as far as Liverpool, under 15 miles away, is a very different job. So is any mileage on the M58, under a mile from Digmoor, where your engine has been working hard the whole time.
Driven till it complained. Knocking, a ragged idle, smoke, a throttle that has gone soft. What you are hearing is your engine reporting fuel that no longer runs like diesel. Leave it wherever it has stopped: a lay-by, a side street, the verge on Beechtrees. Lasting damage is very rare if a car is pulled over soon, and the drain and flush-through that still go first sort it out.
What Digmoor motorists 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 is removed by topping up — you are left with a bigger tank, still the same mix. A diesel fuel system doesn't tolerate petrol by percentage in the way that guidance supposes.
Not so: a current diesel copes with a bit of petrol. If anything, the opposite. More precise parts and higher pressure are the way a modern diesel runs its fuel, and that makes the protection matter more, not less.
Myth: "If it starts and drives, there is no damage done." This is the one that fools people. Feed diesel to a petrol motor and it normally will not run, so the driver stops — and the harm stops with them. Feed petrol to a diesel and it usually starts, ticks over and drives away like nothing happened — all the while its pump wears. Being able to run is not the same as being fine.
Not so: a two-stroke additive lets you to drive home. It is an old fix, supposed for another fault. The petrol is still in the tank afterwards, and what it has weakened is not put back.
"Drain it yourself and you're sorted" — a myth, since after it has been running some petrol sits in the fuel filter and lines, ready to go straight back through the pump on your next start. Also, a can of petrol filled at the roadside is genuinely hazardous.
How does petrol in a diesel take place?
It's rarely carelessness, and nobody does it on purpose. A diesel nozzle mostly won't go into a petrol vehicle, but the smaller petrol nozzle goes into the filler of a diesel nearly without resistance — so forecourts make this one mistake straightforward, and only in that direction.
When routine and your car stop matching, it takes place. A new car, a hire car or a courtesy car. Two vehicles on one driveway, one petrol, one diesel. The pumps in a different order on a well-known forecourt. A train to catch, and a hurried fill en route to Upholland. Precisely the moment it takes place: after years of driving petrol, a driver fills a diesel Volkswagen Golf for the first time. Throw in a back seat full of children, a phone call or rain, and the hand takes over.
Preventing petrol in a diesel next time you fill up around Digmoor
- The label is what matters, and so check the pump instead of the colour: in the UK unleaded handles are normally green and diesel black, but not on every forecourt.
- Check your filler flap. Plenty of cars state the fuel inside the flap or on the cap. Look at it on your first fill in a car you do not know.
- Good intentions count for less than a sticker or a fob in a vivid colour on your diesel's key when a house has one of each. So label it.
- It sounds daft and it does the trick: on your first fill in a new or hired car, say "diesel" out loud before you take the nozzle off the petrol pump.
- While you are thinking about something else, this is an easy mistake to make — so tuck your phone away.
- Up to a point, a misfuel inhibitor helps: some diesels come with a filler designed to block a petrol nozzle, and add-on devices are available for the rest. Count it as a safety net, then keep checking the pump.
- As soon as you notice, stop: less petrol inside the tank means a weaker mixture. What to do next doesn't change, though — still do not crank it.
Petrol already in a diesel in Digmoor? Begin here
The order of things is short, then. Do not start it, and don't turn the ignition on. If you are still at the forecourt — Texaco or anywhere else — ask the staff to help you roll the vehicle clear of the petrol pump. What was put in, roughly how much, and whether it's run: tell us those when you call 0333 366 0103.
Corrosion and deposits form the problem with AdBlue, where petrol means lost lubrication. So if it was AdBlue, say so — and see its own Digmoor page.
Digmoor petrol in a diesel tasks: why one costs more than another
An honest single price doesn't exist here: four situations, four separate jobs. The scenario itself does most of the work of moving your cost. The ratio matters next, meaning how much of the tank is petrol, followed by the location of the car and whether reaching it is safe for a technician.
What went in, how much, and whether it's run — three questions our technicians ask before costing, not after, for exactly that reason. A range turns into a straight figure once those replies are in.
About Digmoor itself
Digmoor is a suburban area in Lancashire, situated near the River Tawd and close to the towns of Skelmersdale and Ormskirk. Digmoor has a mix of housing types, but is predominantly characterised by terraced homes. Digmoor sits at an elevation of 71 metres, and its residents are approximately 12 miles from Liverpool and 179 miles from London.
Digmoor and Lancashire: where our fuel drain cover reaches
Our teams answering petrol in diesel calls in Digmoor, in the WN postcode area, also work the spots near it, Tanhouse, Skelmersdale and East Gillibrands among them. You need not move the car to us. Forecourts, supermarket car parks, lay-bys and your own drive are all spots we drain.
At the petrol pump in Digmoor, still?
The best position there is, then — that is where you are. Turned off it stays; then ring.