Petrol in a Diesel Car in Adswood: How Worried Should You Be?
Far less than you probably are, provided it has not been started. Till the ignition primes your pump, the starter turns, or the car is driven, petrol in a diesel tank simply waits there and does nothing. Which makes the honest reply to that first Adswood query — "have I wrecked it?" — usually no. Petrol in Diesel is who to ring, with your engine left off, so it remains that way. The remainder of this page sets out 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.
Petrol in a diesel: what does it do to the engine?
Passing through a motor, diesel is doing two jobs at once. It burns, and before it burns it protects. What stops the surfaces inside the high-pressure fuel pump and the injectors from grinding against each other is your diesel flowing through them — they are designed to very fine gaps.
Petrol handles the first task badly and the second not at all. The rattling comes from petrol being designed not to ignite when compressed, which is precisely the opposite of what a diesel needs. On top of that it is thinner than diesel, it strips out the lubrication your system hinges on, and any pump running on such a blend is wearing itself.
The shape of the trouble is plain once you put those together. Not contact but movement is what causes the damage. Petrol in a tank is a fuel issue. A pump that has been working on that petrol is the beginning of a mechanical one, and whatever a worn pump sheds travels on with your fuel to your injectors downstream.
Petrol in a diesel in Adswood: how serious is it? Four situations
Filled up, and not started: no case is better. That petrol is inside the tank and just the tank, and the job is a drain and a flush where the vehicle stands. This is the one situation that can only truly happen on a forecourt, as anywhere else the car has been driven to get there.
Ignition on, or started for a moment. With the system primed, the fuel lines and filter now hold petrol that came from your tank. Drain, flush, see to the filter: still normally simple.
Driven a few miles. Now the pump has spent these miles labouring on weakened fuel. Miles is only half of it; how hard it was driven matters equally. Either way the work includes the tank, the lines, your filter and fresh fuel through the whole system. On the school run to St Ambrose Catholic Primary School, the miles is small. Very different again: a trip to Manchester, under 10 miles away, or some miles on the M60, under 3 miles from Adswood, where the motor never stopped running hard.
It protested, and only then stopped: smoke, clattering, a throttle gone soft, an idle gone lumpy. That's your engine telling you its fuel no longer is behaving like diesel. Leave it wherever it stops: a lay-by, a quiet street, the verge on Varden Grove. Long-term damage is very rare if a car is pulled over early, and the fuel drain and flush-through that still come first deal with it.
Adswood drivers and that petrol in a diesel stories they hear
It will not be fine. The myth: "Fill it the rest of the way with diesel and it'll be." Nothing is removed when you top up — the tank just holds more of the same blend. The assumption behind that guidance — that diesel fuel systems accept petrol by percentage — is wrong.
Myth: "A current diesel can cope with a bit of petrol." If anything, the reverse. Smaller components and higher pressure are how a newer diesel runs its fuel, and that makes the lubrication matter more, not less.
This is the one that fools motorists. Myth: "If it starts and drives, there's no harm done." Diesel in a petrol motor normally leaves a motor that won't run: the driver stops, and so does the damage. Whilst your pump grinds, a diesel fed petrol usually starts, idles and drives away as if nothing has happened. Fine and running aren't the same at all.
An old fix for a different fault is behind this one. Myth: "Add some two-stroke oil and drive it home." None of what petrol weakened is put back by it — and later, your tank still contains that petrol.
"Drain it yourself and you're sorted" — a myth, because after it's been running some petrol lies in your filter and lines, waiting to go right back through your pump on the next start. Besides, petrol emptied into a can by the road is genuinely dangerous.
How petrol ends up: petrol in a diesel
Nobody does it on purpose, and it's rarely carelessness. The petrol nozzle is the slimmer of the two and slides into a diesel filler with almost no resistance; a diesel nozzle mostly will not go into a petrol car at all. The forecourt makes it easy, and the error runs one way.
Routine and your car getting out of step is when it takes place. A new car, a hire car or a courtesy car. One petrol and one diesel on the driveway of the same household. A forecourt you know, but with its pumps laid out differently. Rushing for a train outside Davenport and filling up en route. A new-to-you diesel Volkswagen Passat, its first fuelling, and a motorist accustomed to petrol: exactly when it occurs. Throw in rain, a phone call or a back seat full of children, and the hand repeats what it has always done.
How to avoid petrol in a diesel at your next fill-up in Adswood
- Read the pump, not the colour. In the UK unleaded handles are normally green and diesel black, yet not on each forecourt. The label is what matters.
- In a vehicle you don't know, look inside the flap over the filler or at the cap before your first fill: plenty of motors print the fuel type there.
- A coloured fob or a sticker on the diesel's key does more than any amount of meaning to remember, in a home with one of each.
- 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 daft and it does the trick.
- Tuck your phone away. This is an easy mistake to make while you're thinking about something else.
- Some diesels have a filler built to block a petrol nozzle, and devices you can add are available for vehicles without one. Such an inhibitor helps up to a point — as a safety net, not a reason to stop reading the pump.
- Stop as soon as you realise. Less petrol in your tank makes a thinner blend. It doesn't change what to do next, which is still not to start the vehicle.
Already put petrol in a diesel around Adswood?
The order of things is short, then. Never start it, and do not switch your ignition on. Still at the forecourt, at the nearest petrol station or anywhere else? Ask the attendants to help you push it away from the petrol pump. Next, 0333 366 0103. We will ask what went in, about how much, and if it's been run.
If it was AdBlue instead of petrol, say so. That's a different problem — corrosion and deposits rather than lost protection — and it has its own page for Adswood.
What makes one Adswood petrol in a diesel job cost more than the next
There's no honest single price for this, because the four situations above are four different tasks. Chiefly, the cost shifts with which situation you're in. Two things come after that: the petrol that was put in as a proportion of what that tank takes, then the place the vehicle is in and whether a van can reach it safely.
That is why we ask three questions before pricing rather than after: what was put in, how much, and if it's run. A range turns into a straight figure once those answers are in.
About Adswood and where it is
Adswood is a suburban area in Greater Manchester, situated near the lakeside and approximately 68 metres above sea level. Adswood lies close to several nearby places, including Cale Green, Davenport, and Shaw Heath, and is around 6.8 miles from Manchester. Adswood has a population of around 7739 people and is characterised by predominantly semi-detached housing. Adswood is also located a significant distance from London, at around 156 miles away.
Fuel drain cover around Adswood and across Greater Manchester
Adswood rests in the SK postcode area, and our vans that answer petrol in diesel jobs there work the places near it as well — Cale Green, Davenport and Shaw Heath among them. The vehicle does not need to move to us: our engineers drain on a forecourt, in a supermarket car park, in a lay-by or on your own drive.
Adswood: still at the pump?
Then, you could not be in a better spot. Switched off it remains; then phone.