Should You Worry? Petrol in a Diesel Car in Hertford Heath
Less than you probably are, if it hasn't been started. Until the ignition primes the pump, your starter cranks, or the vehicle is driven, petrol in a diesel tank just waits there and does no harm. Which makes the honest reply to that first Hertford Heath query — "have I ruined it?" — usually no. Leave the engine off then ring Petrol in Diesel — that keeps it like that. Read on for three things: the effect petrol has inside a diesel engine, the clues of how far it has got, and ways to make sure you never repeat it.
The engine and petrol in a diesel: what goes on
Two jobs fall to diesel on its journey round a motor. It lubricates first, and only then does it burn. Extremely fine gaps go into your injectors and the high-pressure fuel pump, and only the diesel flowing through keeps those surfaces from grinding together.
The second job petrol does not do at all, and the first it does badly. Being less viscous than diesel, petrol strips away the lubrication a fuel system needs, leaving a pump running on the mixture to wear itself. It is also made to resist igniting under compression — the reverse of what a diesel needs — which is why you hear the clattering.
Together, those make the shape of the issue plain. Not contact but circulation is what causes the damage. All a tank with petrol in it amounts to is a fuel issue. After your pump has been labouring on that petrol, a mechanical fault has started: anything shed by a pump that is wearing is carried onward to the injectors with the fuel.
Four situations our technicians see in Hertford Heath: how bad is petrol in a diesel?
Filled up, and never started: no case is better. Just the tank has petrol in it, so the task is clearing the tank and rinsing your system where your car stands. This scenario can only truly occur at a forecourt: anywhere else, the car got there by being driven.
Ignition on, or started for a second. Your system has been bled, so petrol has left your tank and got to the fuel filter and the lines. Normally little more than draining, rinsing and sorting the fuel filter, so still easy.
A couple of miles driven, and your pump has spent each of them working on weakened fuel. The work is your tank, the fuel lines, the filter and clean fuel through the whole system, and how hard the car was driven counts as much as how far. Short trips, like the school run to Hertford Heath Primary and Nursery School, are one matter. Very different a second time: a trip to St Albans, under 15 miles away, or some miles on the M25, under 10 miles from Hertford Heath, where your engine kept labouring hard.
Knocking, a ragged idle, smoke, a throttle gone soft: driven till it complained. What you are hearing is your motor reporting fuel that no longer acts like diesel. Whether it is the verge on Vicarage Causeway, a lay-by or a side street, stop where you are then leave it. The drain and flush-through still come first, and they deal with it: when a vehicle is pulled over quickly, long-term damage is very unusual.
What Hertford Heath people 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 won't. Nothing is removed when you top up — the tank just carries more of the same blend. A diesel fuel system does not accept petrol by percentage in the way that advice assumes.
Myth: a current diesel copes with a bit of petrol. Rather, the reverse. A current diesel runs its fuel through finer components at higher pressure, which makes the protection count more, not less.
"It starts, it drives, so no harm done" — the myth that catches more drivers than any other. Feed diesel to a petrol engine and it generally will not run, and so the driver stops — and the damage stops with them. A diesel fed petrol usually starts, ticks over and drives away as though nothing has happened, whilst your pump grinds. Running is not the same as fine.
An outdated fix for a different problem is behind this one. Myth: "Add some two-stroke oil and drive the vehicle home." None of what petrol weakened gets put back by it — and later, your tank still contains the petrol.
Myth: "Drain that tank yourself and you're sorted." Once the engine has run, some of that petrol is no longer in that tank: it's in the fuel filter and the fuel lines, and it goes right back through your pump on your next start. It's also truly dangerous to drain petrol into a can at the roadside.
How it happens: petrol in a diesel
No one does it on purpose, and it is rarely carelessness. 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 car at all. The forecourt makes it simple, and the slip runs one way.
Habit and the vehicle falling out of step is when it takes place. Hire cars, courtesy cars, and motors that are new to you. Households running one of each, petrol and diesel. Your usual forecourt, its pumps suddenly in a different order. Rushing for a train outside Hertford East and fuelling up en route. A new-to-you diesel Volkswagen Golf, its first fuelling, and a motorist used to petrol: exactly when it happens. With rain, a call arriving, or children to deal with, your hand simply does what it has always done.
How to avoid petrol in a diesel at your next fill-up around Hertford Heath
- Check 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 counts.
- Plenty of vehicles state the fuel type inside your filler flap or on the cap, so check there on your first fill in any vehicle you don't know.
- Good intentions do less than a sticker or a fob in a vivid colour on your diesel's key if a household has one of each. So mark it.
- "Diesel", out loud, before you pick up the nozzle — every time a new or hired car gets its first tank. It sounds daft. It does the trick.
- Thinking about something else is when this becomes an easy mistake to make, and so tuck your phone away and keep your mind on the pump.
- A misfuel inhibitor helps, up to a point. Some diesels have a filler built to reject a petrol nozzle, and add-on devices exist for motors without one. They are a safety net, not a reason to stop reading the pump.
- As soon as you notice, stop: less petrol inside your tank makes a thinner mix. What to do next does not change, though — still do not fire it up.
Hertford Heath: already put petrol in a diesel?
Then the order of things is brief. Don't turn the ignition on, and don't crank it. If you are still at the forecourt — BP or anywhere else — ask the attendants to help you roll it clear of the petrol pump. Ring 0333 366 0103 next, with three answers — the fuel, the rough quantity, and if it has run.
Say so if it was AdBlue instead of petrol: it is a different problem, with its own page for Hertford Heath, since AdBlue brings corrosion and deposits rather than lost lubrication.
What makes one Hertford Heath petrol in a diesel task cost more than the next
The four scenarios above are four separate tasks, so no single price for this would be honest. Which of them you are in is chiefly what moves the cost. Where the vehicle is matters too, and whether a technician can safely reach it, after the proportion of petrol to what that tank takes.
Three questions come first, before any quote, rather than after — what got in, how much, has it run — and that is the reason. The replies turn a range into a straight figure.
About Hertford Heath, briefly
Hertford Heath is a village in Hertfordshire, situated inland at an elevation of 87 metres, approximately 19.7 miles from London. Hertford Heath lies near several smaller communities, including Rush Green, Pine Hurst, and Woollensbrook, and is close to the city of St Albans, which is 12.8 miles away. Hertford Heath has a population of around 1336 people and is characterised by predominantly terraced housing.
Hertford Heath and Hertfordshire: where our fuel drain cover reaches
Rush Green, Pine Hurst and Woollensbrook are among the places near Hertford Heath that the same teams work, answering petrol in diesel calls across Hertford Heath's SG postcode area. A forecourt, a supermarket car park, a lay-by or your own drive are all places our technicians drain, and your car doesn't need to move to us.
In Hertford Heath and still at the petrol pump?
No position is better: that is where you now are. Keep it off. Phone.