Should You Worry? Petrol in a Diesel Car in Heywood
Unstarted? Then less anxious than you probably feel. Everyone in Heywood starts with "have I ruined it?", and the honest answer is usually no: petrol left in that tank of a diesel stays harmless till priming, cranking or driving draws it into the system. Leave your motor off and call Petrol in Diesel — that keeps it that way. The remainder of this page explains what petrol really does to a diesel, how to judge how far it has got, and how to make sure it does not happen to you again.
Petrol in a diesel: what does it do to your engine?
Diesel does two tasks on its way through a motor. It ignites, and before it burns it protects. Designed to very fine gaps, the injectors and the pump rely on your diesel moving through them to keep their surfaces from wearing against one another.
Petrol does the first task badly and the second not at all. A pump running on a petrol blend is wearing itself out, because petrol is thinner than diesel and takes away the protection the fuel system relies on. Petrol is also designed to resist igniting under compression — the opposite of what a diesel wants from its fuel — and that's where the knocking comes.
Seen together, they show the shape the trouble has. Not contact but movement is what does the damage. Petrol in the tank is a fuel fault. The start of a mechanical one is a pump that has been working on that petrol — and whatever a worn pump sheds moves on with your fuel to the injectors downstream.
How bad is petrol in a diesel? Four scenarios we see in Heywood
Filled but never started — as good as it gets. Just your tank has petrol in it, so the job is draining your tank and purging the system where the vehicle stands. This situation can only really happen on a forecourt: anywhere else, the car got there by being driven.
A brief spell of running, or merely the ignition on. Petrol has left your tank and reached the filter and your lines, since your system has been primed. Still usually simple: drain, flush, and the fuel filter dealt with.
Those few miles on the road were your pump running on fuel diluted by petrol the whole way. Tank, lines, filter, then clean fuel run through the whole circuit: that's this work, and the way your car was driven counts as much as the distance. Driving the children to Harwood Park Primary School is one sort of trip. A run as far as Manchester, under 10 miles away, is a very different job. So is any mileage on the M62, under 3 miles from Heywood, where the engine has been working hard the whole time.
Driven on until it protested — rattling, smoke, a lumpy idle, a soft throttle. The fuel is not behaving 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 Market Street. What comes first is still the fuel drain and flush-through, and that deals with it, with long-term damage very uncommon when a car is stopped soon.
What Heywood motorists get told about petrol in a diesel — and the myths in it
"Top it up the rest of the way with diesel and it will be fine" — a myth. It will not. Topping up removes nothing; it gives you a fuller tank of the same mixture. A diesel fuel system doesn't accept petrol by percentage in the way that advice assumes.
If anything, the reverse is true. Myth: "A current diesel can cope with a bit of petrol." A current diesel runs its fuel through finer components at higher pressure, which makes the lubrication matter more, not less.
Myth: "If it starts and drives, there is no harm done." This is the one that catches motorists. Diesel in a petrol motor normally leaves a motor that will not run: the motorist stops, and so does the harm. Feed petrol to a diesel and it normally fires up, idles and pulls away as if nothing has happened — all while its pump wears. Fine and running are not the same thing.
An outdated fix for a different problem is behind this one. Myth: "Add some two-stroke oil and drive the vehicle home." The petrol is still in your tank after that, and what it has thinned isn't put back.
"Drain it yourself and you are sorted" — a myth, since after it has been running some petrol sits in the filter and lines, ready to go right back through the pump on the next start. It's also really risky to drain petrol into a can at the roadside.
How does petrol in a diesel happen?
It is seldom carelessness, and nobody does it on purpose. The petrol nozzle is the narrower of the two and slides into a diesel filler with almost no resistance; a diesel nozzle generally will not go into a petrol vehicle at all. The forecourt makes it simple, and the mistake runs one way.
Routine and the car falling out of step is how it happens. Hire cars, courtesy cars, and motors that are new to you. One petrol and one diesel on the drive of the same household. The pumps in a different order on a well-known forecourt. Rushing for a train outside Castleton and filling up en route. A new-to-you diesel Volkswagen Golf, its first fuelling, and a motorist used to petrol: exactly when it occurs. Add rain, a phone call or a back seat full of children, and your hand repeats what it has always done.
Next time you fill up around Heywood: preventing petrol in a diesel
- Green for unleaded and black for diesel is normal in the UK — yet not on every forecourt. Trust the label on the pump, not the colour.
- Inspect your filler flap. Many motors state the fuel type inside the flap or on the cap. Look at it on the first fill in any motor you do not know.
- Good intentions do less than a sticker or a fob in a bright colour on your diesel's key when a house has one of each. So label it.
- It sounds silly and it works: on the first fill in a new or hired car, say "diesel" out loud before you lift the nozzle off the pump.
- While you are thinking about something else, this is an easy mistake to make — so put your phone away.
- Up to a point, a misfuel inhibitor helps: some diesels have a filler designed to block a petrol nozzle, and add-on devices exist for the remainder. Count it as a backstop, and keep reading the petrol pump.
- Noticing it mid-fill? Stop there and then. A weaker mix follows from less petrol in your tank, but your next step remains the same: do not start the vehicle.
Put petrol in a diesel in Heywood already?
Then the order of things is short. Starting it is out, and so is turning on your ignition. If you're still on the forecourt — Morrisons or anywhere else — ask the staff to help you push the car clear of the petrol pump. Next, 0333 366 0103. We will ask what was put in, about how much, and if it has been run.
Say so if it was AdBlue instead of petrol: it's a different problem, with its own page for Heywood, because AdBlue brings corrosion and deposits rather than lost protection.
What makes one Heywood petrol in a diesel job cost more than the next
There is no honest single quote for this, because the four situations above are four separate jobs. Which of them you are in is mostly what shifts your cost. Beyond that it is the proportion — how much petrol was put in against how much the tank holds — and then where the vehicle is and whether our van can reach it safely.
That's why our engineers ask three questions before pricing rather than after: what got in, how much, and if it's run. With those answers, you get a straight figure instead of a range.
About Heywood itself
Heywood is a town in Greater Manchester, situated on the River Roch and surrounded by nearby places such as Captain Fold and Back o th Moss. Heywood sits at an elevation of 121 metres, approximately 8 miles north of Manchester, and is characterized by its predominantly terraced housing. Heywood is a significant urban centre in the North West region, with a population of around 23,688 people. Heywood benefits from its proximity to Manchester, while also maintaining its own distinct identity.
Heywood and Greater Manchester: where our fuel drain cover reaches
Heywood waits in the OL postcode area, and the teams that answer petrol in diesel call-outs there work the locations near it as well — Captain Fold, Back o th Moss and Hooley Brow among them. We drain where the car is — your own drive, a lay-by, a supermarket car park, a forecourt — so it does not have to come to us.
Heywood: still at the petrol pump?
Then you're in the best position there can be. Turned off it stays; then ring.