How Worried Should You Be? Petrol in a Diesel Car in Trentham
Far less than you probably are, if it hasn't been started. "Have I wrecked it?" is the first question everyone in Trentham asks, and the honest answer is generally no, because petrol left in a diesel tank harms nothing till it is dragged through the fuel system — by ignition priming, by the starter, or by driving. Keep it like that: leave your motor off then call Petrol in Diesel. The rest of this page explains what petrol really does to a diesel, how to tell how far it has got, and how to make sure it doesn't happen to you again.
Your engine and petrol in a diesel: what happens
On its way through a motor, diesel has two jobs. It protects to begin with, and only then does it burn. The high-pressure pump and your injectors are designed to extremely fine clearances, and the diesel passing through them is what stops those surfaces from wearing down against each other.
The second task petrol does not do at all, and the first it does poorly. Being less viscous than diesel, petrol strips out the protection a fuel system needs, leaving a pump running on the blend wearing itself. It is equally made to resist igniting under compression — the opposite of what a diesel needs — which is where you get the clattering.
Combined, those make the shape of the trouble clear. It's movement that causes the damage, not contact. Where that petrol is only in the tank, it is a fault of fuel, nothing more. Whatever a worn pump sheds travels on, borne by your fuel, into the injectors further along, which is why a pump that has been working on the petrol is where a mechanical problem starts.
How bad is petrol in a diesel? Four scenarios our engineers see in Trentham
The best case there can be: filled up, never started. The petrol is inside the tank and just that tank, and the task is a drain and a flush where the vehicle sits. This is the one scenario that can only truly take place at a forecourt, because anywhere else your car has been driven to get there.
Started for a moment, or only the ignition on. With the system primed, your lines and filter already contain petrol that came from the tank. Drain, flush, see to the fuel filter: still normally simple.
The pump now worked a couple of miles on thinned fuel — that's what driving the car meant. How hard the vehicle was driven counts as much as how far, and this work takes in your tank, your lines, the filter and clean fuel through the entire system. On the school run to Ash Green Primary Academy, the mileage is short. Getting as far as Stoke-on-Trent, under 5 miles away, makes a very different job — as does any distance on the M6, under 3 miles from Trentham, with the engine labouring hard all the way.
Driven on till it protested — rattling, smoke, an uneven idle, a dead throttle. What you are hearing is your motor reporting fuel that no longer acts like diesel. Whether it's the verge on New Inn Lane, a lay-by or a side street, stop where you are and leave it. Long-term damage is very uncommon when a vehicle is stopped early, and the fuel drain and flush-through that still come first deal with it.
What Trentham drivers get told about petrol in a diesel — and the stories 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 bigger tank of the same mixture. A diesel fuel system does not tolerate petrol by percentage in the way that guidance presumes.
If anything, the reverse holds. Myth: "A current diesel can cope with a bit of petrol." At higher pressure, through smaller parts: that's how a modern diesel handles its fuel, and so the lubrication counts for more, not less.
Myth: "If it starts and drives, there's no harm done." This is the one that catches people. Diesel in a petrol motor usually leaves a motor that won't run: the driver stops, and so does the damage. A diesel fed petrol generally starts, ticks over and drives away as if nothing has happened, while your pump wears. Running is not the same as fine.
An old workaround for a different problem is behind this one. Myth: "Add some two-stroke oil and drive the vehicle home." It doesn't put back what petrol has thinned, and that petrol is still inside that tank after that.
Myth: "Drain that tank yourself and you are sorted." Once the engine has run, some of the petrol is no longer inside that tank: it's in your filter and the lines, and it goes straight back through the pump at your next start. And, a can of petrol drained at the kerbside is genuinely risky.
How petrol ends up: petrol in a diesel
Nobody does it on purpose, and it's rarely carelessness. One way only, since of the nozzles: the smaller petrol one slips inside a diesel filler with almost no resistance, whereas the diesel one mostly won't fit a petrol motor. That is how the forecourt makes it straightforward.
It happens when routine and your car stop matching. Hire cars, courtesy cars, and cars that are new to you. One petrol and one diesel on the drive of the same household. A well-known forecourt with the pumps in a different order. Rushing for a train outside Wedgwood and fuelling up en route. Years of petrol vehicles behind you, a diesel Volkswagen Passat in front of you at the forecourt for its first tank — that is when. The hand does what it has always done when you add rain, a phone call or a back seat full of children.
How to avoid petrol in a diesel on your next fill-up in Trentham
- 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.
- Inspect the filler flap. Plenty of cars state the fuel type inside the flap or on the cap. Look at it on the first fill in a vehicle you do not know.
- One of each in the house? Mark your key to the diesel — a coloured fob, a sticker — since intending to remember isn't enough.
- Before the nozzle leaves the petrol pump the first time you fuel a hired or new vehicle, say "diesel" out loud. Daft, perhaps, but it works.
- Thinking about something else is when this becomes an easy mistake to make, and so put the phone away and keep your mind on the petrol pump.
- Some diesels have a filler designed to reject a petrol nozzle, and devices you can add exist for vehicles without one. Such an inhibitor helps up to a point — as a backstop, not a reason to stop checking the petrol pump.
- Less petrol means a weaker mixture, so stop as soon as you notice — though remembering that the next stage is unchanged. It's still not to fire it up.
Already put petrol in a diesel around Trentham?
Short and simple, then, is the order of things. Starting it is out, and so is switching on your ignition. Still at the forecourt, at BP or anywhere else? Ask the staff to help you push the vehicle away from the petrol pump. Phone 0333 366 0103 next, with three answers — your fuel, the approximate amount, and whether it has run.
Corrosion and deposits form the problem with AdBlue, whereas petrol means lost protection. So if it was AdBlue, say so — and read its own Trentham page.
Why one petrol in a diesel task in Trentham costs more than another
Four different tasks lie behind the four situations above — which is why there's no fair single price. Chiefly, your cost moves with which one you're in. Where your car is counts too, and whether our van can safely get to it, after the share of petrol to what your tank takes.
Ahead of any quote, not after, come three queries: your fuel that got in, the amount, and whether it's run. That's why. Given those answers, there is a straight figure instead of a range.
About Trentham itself
Trentham is a suburban area in Staffordshire, situated on the River Trent at an elevation of 111 metres, with Stoke-on-Trent just 3.9 miles away. Trentham has a mix of housing types, but detached homes are predominant, and the area is close to nearby places like Hem Heath and Hanford. Trentham is located in the West Midlands region, approximately 133.2 miles from London. Trentham's riverside setting contributes to its character as a residential area.
Trentham and Staffordshire: where our fuel drain cover reaches
Petrol in diesel call-outs in Trentham — part of the ST postcode area — go to vans that likewise cover the places about it, Hem Heath, Hanford and Sideway included. No need to bring your vehicle to us. Forecourts, supermarket car parks, lay-bys and your own drive are all locations where we work.
Trentham: still at the pump?
Then, you couldn't be in a better spot. Ring, and leave it turned off.