Petrol in a Diesel Car in Warbreck: How Worried Should You Be?
Less than you probably are, provided it hasn't been started. Everyone around Warbreck begins with "have I wrecked it?", and the fair answer is usually no: petrol left in that tank of any diesel remains harmless till priming, cranking or driving draws it into your fuel system. Petrol in Diesel is who to call, with the motor kept off, and so it remains that way. The rest of this page sets out what petrol really does to a diesel, how to tell how far it has got, and how to make sure it doesn't happen to you a second time.
Petrol in a diesel: what does it do to your engine?
Passing through an engine, diesel is doing two jobs at once. It protects first, and only then does it burn. Built to very fine clearances, the injectors and your pump depend on the diesel moving through them to keep their surfaces from wearing against one another.
Badly at the first, not at all at the second: that's petrol. A pump running on a petrol mix is wearing itself out, since petrol is runnier than diesel and strips out the lubrication the fuel system depends on. Petrol is also made to resist igniting under compression — the reverse of what a diesel needs from its fuel — and that's where the knocking comes.
Put those together and the shape of the trouble is plain. Not contact but movement is what does the damage. A tank with petrol in it is a fuel problem. The start of a mechanical problem is a pump that has been working on that petrol — and whatever a worn pump sheds moves on with your fuel to the fuel injectors downstream.
Four situations our engineers see in Warbreck: how serious is petrol in a diesel?
Filled but never started — the best it gets. At a forecourt, and genuinely only there, that petrol is still limited to that tank — since anywhere else your car was driven to reach it. The job is draining and rinsing on the spot.
A brief spell of running, or merely the ignition on. With the system primed, the fuel lines and filter now contain petrol that has come from that tank. Normally little more than emptying, purging and sorting the fuel filter, and so still simple.
Driven a couple of miles. Now the pump has spent these miles labouring on weakened fuel. The work is your tank, the lines, the filter and fresh fuel through the whole system, and how hard the vehicle was driven counts as much as how far. Driving the kids to Holy Family Catholic Primary School is one kind of trip. Very different again: a trip to Preston, under 15 miles away, or some distance on the M55, under 5 miles from Warbreck, where the engine never stopped labouring hard.
Rattling, a ragged idle, smoke, a throttle gone soft: driven until it complained. The fuel is not acting like diesel any more, and the motor is saying so. Leave it where it has stopped: a lay-by, a side street, the verge on Hilstone Lane. The drain and flush still go first, and they take care of it: when a car is stopped soon, long-term damage is very unusual.
What Warbreck motorists get told about petrol in a diesel — and the stories 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. The idea behind the advice — that diesel fuel systems tolerate petrol by percentage — is wrong.
Not so: a newer diesel copes with a bit of petrol. If anything, the reverse. A modern diesel runs its fuel through more precise components at higher pressure, which makes the protection count more, not less.
This is the one that catches people. Myth: "If it starts and drives, there's no damage done." Any petrol motor fed diesel normally will not run, so the motorist stops and the harm stops with them. Whilst the pump wears, a diesel fed petrol usually starts, idles and drives away as if nothing has happened. Running is not the same as fine.
Not so: a two-stroke additive lets you to drive home. It was an old workaround, supposed for another fault. The petrol is still inside the tank afterwards, 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 filter and lines, ready to go right back through the pump at your next start. It is also truly hazardous to drain petrol into a can by the roadside.
Petrol in a diesel: how does it occur?
Nobody does it on purpose, and it is rarely carelessness. The forecourt makes it simple: the petrol nozzle is the narrower of the two, and it slips into a diesel filler with almost no resistance, whilst a diesel nozzle generally will not go into a petrol vehicle at all. So the error runs one way.
It occurs when routine and the car stop matching. A vehicle that's new to you — hired, on loan as a courtesy car, or just bought. Two vehicles on one driveway, one petrol, one diesel. The pumps in a different order on a well-known forecourt. A hurried fill on the way to Layton with a train to catch. The first fill-up in a diesel Volkswagen Tiguan after years of driving petrol is exactly the moment it occurs. Your hand repeats what it has always done once you add rain, a phone call or a back seat full of kids.
How to prevent petrol in a diesel on your next fill-up around Warbreck
- Not every forecourt in the UK keeps to green for unleaded and black for diesel, even if most usually do. Read the petrol pump's label; the colour is only a clue.
- In a vehicle you don't know, look inside the flap over your filler or at the cap before your first fill: many motors state the fuel there.
- Good intentions count for less than a sticker or a fob in a bright colour on the diesel's key if a home has one of each. So label it.
- "Diesel", aloud, before you lift the nozzle — each time a new or hired car gets its first tank. It sounds silly. It does the trick.
- Put the phone away. This is an easy mistake to make whilst you are thinking about something else.
- Add-on devices exist for vehicles without one, and some diesels come with a filler that will not accept a petrol nozzle. Useful — but a safety net at best, never a reason to stop checking the label.
- Noticing it halfway? Stop at once. A weaker mix results from less petrol inside your tank, but the next stage remains the same: do not start the car.
Petrol already in a diesel around Warbreck? Begin here
Short and simple, then, is the order of things. Leave it unstarted, with your ignition off as well. The staff at the forecourt — whether at Texaco itself or wherever you filled up — will usually help push it clear of the pump if you ask. Then ring 0333 366 0103 and tell us what was put in, about how much, and if it's run.
Corrosion and deposits are the issue with AdBlue, whereas petrol brings lost protection. So if it was AdBlue, say so — and read its own Warbreck page.
What makes one Warbreck petrol in a diesel job cost more than the next
There is no honest single price for this, since the four situations above are four different tasks. The situation itself does most of the work of moving the cost. Two things come after that: the petrol that was put in as a proportion of what that tank takes, then the place your car is in and whether a van can reach it safely.
That is why our engineers ask three queries before costing instead of after: what went in, how much, and whether it's run. Those answers change a range into a straight figure.
About Warbreck and where it is
Warbreck is a suburban area in Lancashire, situated on the coast at an elevation of around 25 metres, with semi-detached housing being the predominant type of accommodation. Warbreck lies near several other local places, including Hoohill, North Shore, and Layton, and is approximately 14.7 miles from the city of Preston. Warbreck is also relatively close to the larger urban areas of the North West region, while still being some distance from London, at around 201.8 miles away. Warbreck has a population of around 6061 people, making it a small but established community.
Fuel drain cover around Warbreck and across Lancashire
Hoohill, North Shore and Layton are among the places near Warbreck that the same teams work, answering petrol in diesel jobs across Warbreck's FY postcode area. Our technicians drain where your vehicle is — your own driveway, a lay-by, a supermarket car park, a forecourt — so it does not have to come to us.
In Warbreck and still at the pump?
In that case, you couldn't be in a better position. Keep the vehicle switched off, then ring.