Petrol in a Diesel Car in West Watford: How Worried Should You Be?
Not started? Then less anxious than you likely feel. Until your ignition primes your pump, the starter cranks, or the vehicle is driven, petrol in a diesel tank just sits there and does no harm. Which makes the truthful reply to the first West Watford query — "have I wrecked it?" — usually no. Keep it that way: leave your motor off and ring Petrol in Diesel. Further down, this page sets out what petrol really does inside a diesel, how far it may have gone, and how to stop it happening to you a second time.
Petrol in a diesel: what does it do to your engine?
On its way through a motor, diesel does two jobs. It burns, and before it combusts it protects. Extremely fine tolerances go into the fuel injectors and the high-pressure pump, and just the diesel running through stops those surfaces grinding together.
The second task petrol does not do at all, and the first it does badly. It's thinner than diesel and strips away the protection the system rests on, so a pump running on a petrol blend is a pump wearing itself. And petrol is designed to resist igniting under compression, which is the reverse of what a diesel needs from its fuel. That is where the rattling comes from.
Taken together, they show the shape the problem has. It is circulation that does the harm, not contact. Petrol in the tank is a fuel problem. The start of a mechanical one is a pump that has been labouring on that petrol — and whatever a worn pump sheds moves on with your fuel to the injectors beyond it.
West Watford, petrol in a diesel: four cases, from mild to major
The best case there can be: filled up, never started. The petrol is inside that tank and just your tank, and the job is a drain and a flush where your car sits. This is the one scenario that can only truly take place at a forecourt, because anywhere else the car has been driven to get there.
The ignition turned on, or a brief start. Petrol has come out of that tank and got to your filter and your lines, because the system has been primed. That's generally still a straightforward task — a drain, a flush, and the filter seen to.
Driven a couple of miles. Now your pump has spent these miles working on diluted fuel. The work is your tank, your lines, the filter and fresh fuel through the entire circuit, and how hard the vehicle was driven matters as much as how far. Driving the kids to Chater Infant School is one kind of trip. Very different once more: a trip to St Albans, under 10 miles away, or any distance on the M1, under 3 miles from West Watford, where the motor kept labouring hard.
Driven on until it protested — clattering, smoke, a lumpy idle, a soft throttle. The engine is telling you the fuel is no longer behaving like diesel. Pull up where you are — on the verge on Queens Avenue, at the kerb, down a side road — and don't move it. A vehicle stopped early very seldom has permanent damage, since the fuel drain and the flush, which still go first, deal with it.
What West Watford drivers get told about petrol in a diesel — and the myths in it
Myth: "Fill it the rest of the way with diesel and it will be fine." It will not. Topping up removes nothing; it gives you a fuller tank of the same mix. A diesel fuel system does not accept petrol by percentage in the way that advice supposes.
Not so: a current diesel copes with a bit of petrol. Rather, the reverse. More precise components and higher pressure are the way a modern diesel runs its fuel, and that makes the protection matter more, not less.
This is the one that fools people. Myth: "If it starts and drives, there is no harm done." A petrol motor fed diesel normally will not run, and so the driver stops and the harm stops with them. Nothing looks to have happened when a diesel fed petrol fires up, ticks over and drives away, as it usually will; meanwhile the pump wears. A running engine does not mean fine.
"A drop of two-stroke oil and drive it home" — a myth, borrowed from a fix from years ago, for a distinct problem. It doesn't put back what petrol has thinned, and the petrol is still in that tank after that.
Once your engine has run, part of that petrol is in the fuel filter and the lines, not the tank — and your next start sends it straight back through your pump. So the myth "drain your tank yourself and you are sorted" does not stand up. On top of that, petrol emptied into a can by the road is genuinely dangerous.
Why petrol in a diesel occurs so easily
On purpose? Never. Through carelessness? Seldom, if ever. A diesel nozzle mostly will not fit a petrol vehicle, yet the narrower petrol nozzle goes into the filler of a diesel nearly without resistance — so forecourts make this one mistake easy, and just in one direction.
When routine and the car stop matching, it occurs. A new motor, a hire car or a courtesy car. A household with one petrol and one diesel on the driveway. A familiar forecourt with the pumps in a different order. A rushed fill en route to Watford High Street with a train to catch. The first fill-up in a diesel Volkswagen Golf after years of driving petrol is exactly the moment it takes place. The hand does what it has always done once you add rain, a phone call or a back seat full of children.
Next time you fill up around West Watford: preventing petrol in a diesel
- Read the pump, not the colour. In the UK unleaded handles are normally green and diesel black, but not on each forecourt. The label is what matters.
- The first fill in a strange car is the time to check the filler flap — inside it, or on the cap, many motors state the fuel they take.
- A coloured fob or a sticker on the diesel's key achieves more than any amount of intending to remember, in a household with one of each.
- Say it before you lift it. On the first fill in a new or hired car, say "diesel" out loud before you lift the nozzle off the pump. It sounds daft and it does the trick.
- Put your phone away. This is an easy mistake to make while you're thinking about something else.
- 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. Treat it as a backstop, and keep reading the petrol pump.
- Less petrol means a weaker mix, and so stop as soon as you notice — while remembering that the next step is unchanged. It is still not to fire it up.
Already put petrol in a diesel in West Watford?
The order of things is short, then. Don't turn the ignition on, and don't crank it. Ask the staff to help you push it clear of the petrol pump if you're still at the forecourt, whether that is BP or anywhere else. Then ring 0333 366 0103 and tell us what was put in, roughly how much, and whether it's run.
Corrosion and deposits are the issue with AdBlue, where petrol brings lost lubrication. So if it was AdBlue, say so — and read its own West Watford page.
West Watford petrol in a diesel tasks: why one costs more than another
There is no honest single price for this, since the four situations above are four separate tasks. What shifts the cost is mostly which of them you're in. After that it's the ratio — how much petrol went in against how much the tank holds — and after that where your car is and whether our van can reach it safely.
Three queries come first, before quoting, rather than after — what was put in, how much, has it run — and this is the reason. Those replies are what turn a range into one firm number.
About West Watford and its setting
West Watford is a suburban area in Hertfordshire, situated approximately 15.8 miles northwest of London and 7.6 miles southeast of St Albans. West Watford sits at an elevation of around 69 metres, characterised by its predominantly terraced housing stock. West Watford is located near other local places such as Holywell, Watford, and The Rookery, and has a population of around 13997 residents.
West Watford and Hertfordshire: where our fuel drain cover reaches
Our teams answering petrol in diesel jobs around West Watford, in the WD postcode area, also work the spots around it, Holywell, Watford and The Rookery among them. The vehicle does not need to come to us: our engineers drain at a forecourt, in a supermarket car park, in a lay-by or on your own driveway.
Still at the petrol pump around West Watford?
The best place there is, then — that is where you are. Keep the vehicle switched off, and ring.