How Worried Should You Be? Petrol in a Diesel Car in Tarvin
Unstarted? Then less worried than you probably feel. Petrol sitting in a diesel tank does nothing to your motor until something pulls it through your fuel system — the ignition priming the pump, the starter, or the drive on its own. So the honest answer to the first question everyone around Tarvin asks, "have I ruined it?", is normally no. Keep it that way: leave the engine off then phone Petrol in Diesel. Read on for three things: the effect petrol has inside a diesel motor, the clues of how far it has spread, and ways to make sure you never repeat it.
Your engine and petrol in a diesel: what goes on
Passing through a motor, diesel is doing two jobs at once. It lubricates first, and only then does it burn. Very fine gaps go into the injectors and the high-pressure fuel pump, and just your diesel running through stops their surfaces grinding together.
Petrol handles the first task poorly and the second not at all. The rattling comes from petrol being designed not to ignite when compressed, which is precisely the reverse of what a diesel needs. On top of that it is runnier than diesel, it strips away the lubrication the system rests on, and any pump running on that blend is wearing itself.
Put these together and the shape of the trouble is clear. It is movement that does the harm, not contact. All a tank with petrol in it amounts to is a fuel problem. The start of a mechanical one is a pump that has been running on that petrol — and whatever a worn pump sheds travels on with your fuel to the injectors downstream.
Petrol in a diesel in Tarvin: how serious is it? Four situations
Fuelled up, never started. The best case there is. At a forecourt, and really only there, that petrol is still limited to the tank — since everywhere else your car was driven to get to it. The task is emptying and rinsing on the spot.
Ignition on, or started for a second. Petrol has come out of that tank and got to your filter and your lines, since your system has been primed. Normally nothing more than draining, purging and seeing to your filter, and so still easy.
A couple of miles driven, and the pump has spent each of them labouring on weakened fuel. The work is your tank, the lines, your filter and fresh fuel through the whole circuit, and how hard the vehicle was driven matters as much as how far. Driving the kids to Tarvin Primary School is one kind of trip. Any distance on the M53, under 5 miles from Tarvin, means the motor working hard throughout, and a run to Chester, under 10 miles away, is a very different task as well.
It protested, and only then stopped: smoke, rattling, a throttle gone soft, an idle gone lumpy. The engine is telling you your fuel is no longer acting like diesel. Pull up wherever you are — the verge on High Street, a lay-by, a side street — and leave the car there. What goes first is still the fuel drain and flush-through, and that takes care of it, with permanent damage very rare when a vehicle is pulled over quickly.
Petrol in a diesel myths Tarvin people hear
Myth: "Fill it the rest of the way with diesel and it will be fine." It will not. Nothing is removed when you top up — your tank simply carries more of the same blend. 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. Rather, the opposite. Smaller parts and higher pressure are the way a newer diesel runs its fuel, and that makes the protection count more, not less.
Myth: "If it starts and drives, there is no harm done." This is the one that fools drivers. Diesel in a petrol motor usually means a motor that will not run: the motorist stops, and so does the damage. While your pump grinds, a diesel fed petrol usually starts, idles and drives away as though nothing has happened. Fine and running are not the same at all.
An outdated workaround for a separate fault is behind this one. Myth: "Add some two-stroke oil and drive the car home." None of what petrol diluted is put back by it — and later, your tank still holds the petrol.
The next start draws petrol back round your pump from your lines and the fuel filter, where some of that ends up after your engine has run. That is why draining the tank yourself doesn't leave you sorted — a myth. Also, a can of petrol drained at the roadside is truly dangerous.
How petrol ends up: petrol in a diesel
No one does it on purpose, and it is seldom carelessness. The forecourt makes it easy: the petrol nozzle is the smaller of the two, and it slides into a diesel filler with almost no resistance, whilst a diesel nozzle generally won't go into a petrol car at all. So the slip runs one way.
The moment routine stops matching your car is the moment it takes place. Any motor that is new to you — hired, on loan as a courtesy car, or brand new. Two motors on one drive, one petrol, one diesel. A well-known forecourt with the pumps in a different order. A train to catch, and a rushed fill en route to Mouldsworth. A new-to-you diesel Volkswagen Golf, its first fuelling, and a driver accustomed to petrol: exactly when it occurs. Add rain, a phone call or a back seat full of kids, and the hand repeats what it has always done.
Next time you fill up around Tarvin: avoiding petrol in a diesel
- Not every forecourt in the UK follows green for unleaded and black for diesel, even if most usually do. Check the petrol pump's label; the colour is only a clue.
- Check the filler flap. Many motors state the fuel type inside the flap or on the cap. Look at it on your first fill in any motor you do not know.
- Mark your key. In a house with one of each, a coloured fob or a sticker on the diesel's key does more than any amount of intending to remember.
- Say it before you lift it. On the first fill in a new or hired car, say "diesel" aloud before you lift the nozzle off the petrol pump. It sounds silly and it works.
- Thinking about something else is when this becomes an easy mistake to make, so put the phone away and keep your mind on the petrol pump.
- Up to a point, a misfuel inhibitor helps: some diesels come with a filler built to reject a petrol nozzle, and aftermarket devices are available for the rest. Count it as a safety net, and keep reading the petrol pump.
- As soon as you notice, stop: less petrol in your tank makes a weaker mix. What to do next doesn't change, though — still don't crank it.
Tarvin: already put petrol in a diesel?
Then the order of things is short. Do not fire it up, and do not turn your ignition on. Yet at the forecourt, at BP or anywhere else? Ask the attendants to help you roll it away from the petrol pump. Then call 0333 366 0103 and tell us what was put in, roughly how much, and whether it's run.
Corrosion and deposits form the problem with AdBlue, whereas petrol brings lost protection. So if it was AdBlue, say so — and read its own Tarvin page.
What makes one Tarvin petrol in a diesel job cost more than the next
There's no honest single price for this, since the four scenarios above are four separate jobs. Which of them you're in is mostly what shifts the cost. Where the car is matters too, and whether our van can safely reach it, after the share of petrol to what your tank takes.
That is why our engineers ask three questions before pricing rather than after: what got in, how much, and whether it has run. Given the replies, you get a straight figure rather than a range.
About Tarvin, for a moment
Tarvin is a village in Cheshire, situated on the River Gowy at an elevation of around 35 metres, with nearby areas including Tarvin Sands and Oscroft. Tarvin lies close to the city of Chester, approximately 5 miles to the west, and is characterized by its semi-detached housing stock. Tarvin remains a small, rural community with a population of around 1365 people, set within the North West region of England. Tarvin is also near Hollowmoor Heath, a local area of natural interest.
Fuel drain cover across Cheshire, Tarvin included
Tarvin waits in the CH postcode area, and the teams that answer petrol in diesel call-outs there work the spots near it as well — Tarvin Sands, Oscroft and Hollowmoor Heath among them. Our technicians drain wherever your car is — your own drive, a lay-by, a supermarket car park, a forecourt — so it never needs to come to us.
At the petrol pump in Tarvin, still?
No position is better: that's where you are. Keep it switched off, then ring.