How Worried Should You Be? Petrol in a Diesel Car in Maylandsea
Provided it hasn't been started, worry far less than you probably are. "Have I ruined it?" is the first thing anyone around Maylandsea asks, and the truthful answer is usually no, because petrol left in a diesel tank harms nothing till it's dragged through your fuel system — by ignition priming, by your starter, or by being driven. Keep it like that: leave your engine off then phone Petrol in Diesel. What petrol actually does to a diesel, how to gauge how far it's travelled, and how to stop it from happening a second time: that is the rest of this page.
Your engine and petrol in a diesel: what happens
Passing through a motor, diesel is doing two jobs at once. It lubricates to begin with, and only then does it burn. Extremely fine gaps are built into your injectors and the high-pressure pump, and only your diesel running through keeps their surfaces from grinding together.
The second task petrol doesn't do at all, and the first it does poorly. Being less viscous than diesel, petrol strips away the protection a fuel system needs, leaving a pump on the mixture wearing itself. It's equally made to resist igniting under compression — the reverse of what a diesel needs — which is why you get the rattling.
Put these together and the shape of the problem is plain. It is circulation that does the damage, not contact. Petrol in a tank is a fuel fault. The beginning of a mechanical one is a pump that has been running on that petrol — and whatever a worn pump sheds moves on with your fuel to the injectors downstream.
Four situations our technicians see around Maylandsea: how serious is petrol in a diesel?
Filled up, and never started: no case is better. Only that tank has petrol in it, so the task is draining your tank and purging the fuel system where the car stands. This situation can only truly occur at a forecourt: anywhere else, your car got there by being driven.
Ignition on, or started for a moment. Petrol has come out of the tank and reached the fuel filter and the fuel lines, because the system has been primed. That is usually still a straightforward job — a drain, a flush, and the filter dealt with.
Driven a few miles. Now the pump has spent those miles running on thinned fuel. Mileage is only half of that; how hard it was driven counts just as much. Either way this work runs to the tank, the lines, your filter and fresh fuel through the whole system. Driving the kids to Maylandsea Primary School is one sort of trip. A run as far as Southend-on-Sea, under 15 miles away, is a very different job. So is any distance on the M25, under 25 miles from Maylandsea, where your engine has been running hard the whole time.
Driven on till it protested — clattering, smoke, an uneven idle, a soft throttle. That is the motor telling you its fuel no longer is behaving like diesel. Pull up where you are — on the verge on Marine Parade, at the kerb, down a side road — and don't move it again. Long-term damage is very uncommon when a vehicle is stopped quickly, and the fuel drain and flush-through that still go first take care of it.
Myths Maylandsea people hear about petrol in a diesel
"Top it up the rest of the way with diesel and it'll be fine" — a myth. It will not. A fuller tank of the same mix is all you get, because topping up takes out nothing. Percentage is not how a diesel fuel system copes with petrol, whatever that guidance presumes.
If anything, the reverse holds. Myth: "A modern diesel can cope with a bit of petrol." A current diesel sends its fuel through more precise components at higher pressure, which makes the lubrication count more, not less.
Myth: "If it starts and drives, there's no harm done." This is the one that fools people. A petrol motor fed diesel usually will not run, so the motorist stops and the damage stops with them. A diesel fed petrol generally starts, ticks over and drives away as though nothing has happened, while your pump wears. A running engine does not mean fine.
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 thinned is put back by it — and later, that tank still holds that petrol.
Myth: "Drain your tank yourself and you're sorted." After your engine has run, some of the petrol is no longer in your tank: it is in your filter and your lines, and it goes straight back through the pump on the next start. And, a can of petrol drained by the kerbside is genuinely hazardous.
Why petrol in a diesel occurs at all
Carelessness is rarely the cause, and no one means to do it. A diesel nozzle mostly will not fit a petrol motor, yet the narrower petrol nozzle goes into the filler of a diesel almost without resistance — so forecourts make this one error straightforward, and just in one direction.
It takes place when routine and your car stop matching. Hire cars, courtesy cars, and motors that are new to you. Households running one of each, petrol and diesel. A well-known forecourt with the pumps in a different order. A rushed fill en route to Althorne with a train to catch. Exactly the moment it takes place: after years of driving petrol, someone fills a diesel Renault Megane for the first time. With rain, a call arriving, or children to deal with, your hand simply does what it has always done.
Maylandsea drivers: how to prevent petrol in a diesel next time
- Green for unleaded and black for diesel is usual in the UK — but not on each forecourt. Go by the label on the petrol pump, not the colour.
- Inspect the filler flap. Many motors state the fuel inside the flap or on the cap. Look at it on your first fill in any motor you don't know.
- Good intentions do less than a sticker or a fob in a bright colour on your diesel's key when a household has one of each. So mark it.
- 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 pump. It seems daft and it does the trick.
- Mistakes like this are easy to make whilst your mind is on something else, and so your phone goes away.
- A misfuel inhibitor helps, up to a point. Some diesels have a filler built to block a petrol nozzle, and add-on devices are available for cars without one. They are a backstop, not a reason to stop reading the petrol pump.
- Stop the moment you notice. Less petrol in the tank means a thinner mix. It doesn't change what to do next, which is still not to fire it up.
Petrol already in a diesel in Maylandsea? Start here
Then the order of things is short. Do not switch the ignition on, and do not fire it up. Still on the forecourt, at Texaco or anywhere else? Ask the staff to help you push it away from the petrol pump. Next, 0333 366 0103. We will ask what was put in, roughly how much, and if it's been run.
AdBlue, not petrol? Then say so. Corrosion and deposits, not lost lubrication, make it a different fault — Maylandsea has a page just for it.
Maylandsea petrol in a diesel tasks: why one costs more than another
The four scenarios above are four separate tasks, so no single quote for this would be fair. The situation itself does most of the work of moving the cost. The share counts next, meaning how much of your tank is petrol, and then the location of the vehicle and whether getting to it is safe for a technician.
That's why our engineers ask three questions before pricing rather than after: what was put in, how much, and whether it has run. A range becomes a straight figure when those answers are in.
About Maylandsea, for a moment
Maylandsea is a small coastal village in Essex, situated near the River Blackwater estuary and close to the nearby settlements of Mayland, Althorne, and Latchingdon. Maylandsea has a low elevation of around 11 metres above sea level and is located approximately 39.8 miles from London. Maylandsea is characterised by its predominantly detached housing stock, reflecting its development as a residential area. Maylandsea is also near the city of Southend-on-Sea, which is about 10.3 miles away.
Across Essex and around Maylandsea: fuel drain cover
The teams answering petrol in diesel calls in Maylandsea, in the CM postcode area, also work the locations around it, Mayland, Althorne and Latchingdon included. You need not move your car to us. Forecourts, supermarket car parks, lay-bys and your own drive are all spots where we work.
Still at the petrol pump in Maylandsea?
Then, you could not be in a better place. Switched off it stays; then ring.