How Worried Should You Be? Petrol in a Diesel Car in Silverbank
Provided it has not been started, you can worry less than you probably are. "Have I wrecked it?" is the first thing everyone around Silverbank asks, and the honest answer is normally no, because petrol resting in a diesel tank hurts nothing until it's dragged through your fuel system — by ignition priming, by the starter, or by being driven. Petrol in Diesel is who to call, with your motor left off, so it remains that way. What petrol actually does to a diesel, how to gauge how far it's gone, and how to stop it from happening a second time: that's the remainder of this page.
Petrol in a diesel: what does it do to your engine?
Diesel has two tasks on its way through an engine. Before it burns, it lubricates — and then it combusts. Built to very fine gaps, the injectors and your pump rely on your diesel moving through them to stop their surfaces wearing against one another.
Of those two jobs, petrol manages the first poorly and the second never. A pump working on a petrol blend is wearing itself out, because petrol is thinner than diesel and strips out the lubrication your fuel system depends on. Petrol is also designed to resist igniting under compression — the reverse of what a diesel wants from its fuel — and that is where the knocking comes.
Taken together, they make clear what shape the issue has. It's movement that causes the harm, not contact. All a tank with petrol in it amounts to is a fuel fault. The beginning of a mechanical problem 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 our engineers see around Silverbank
Filled up, and not started: no case is better. Being at a forecourt is what makes this the case: elsewhere, the vehicle has been driven there to begin with. With that petrol kept in your tank alone, it's emptied and flushed on the spot, and nothing more is needed.
Started for a second, or only your ignition on. Once primed, the system has pulled petrol from that tank up to your filter and the fuel lines. That is generally still a straightforward job — a drain, a flush, and the fuel filter dealt with.
Those few miles on the road were your pump labouring on fuel diluted by petrol the whole way. Distance is only half of that; how hard it was driven matters equally. Either way the work includes that tank, the fuel lines, your filter and fresh fuel through the whole system. Driving the kids to the local primary school is one kind of trip. Very different again: a run to Aberdeen, under 25 miles away, or any mileage on the M90, over 50 miles from Silverbank, where the motor never stopped running hard.
It complained, and only then stopped: smoke, clattering, a throttle gone soft, an idle gone lumpy. What you are hearing is the engine reporting fuel that no longer behaves like diesel. Whether it's the verge on Pantoch Gardens, a lay-by or a side road, stop where you are and leave it. Permanent damage is very unusual when a car is pulled over soon, and the drain and flush that still go first take care of it.
Silverbank motorists and that petrol in a diesel stories they hear
It will not be fine. The myth: "Fill it the rest of the way with diesel and it'll be." Nothing is removed by topping up — you are left with a bigger tank, still the same mixture. The assumption behind the advice — that diesel fuel systems accept petrol by percentage — is wrong.
If anything, the reverse is true. Myth: "A current diesel can cope with a bit of petrol." Lubrication matters more on modern diesels, not less, because their fuel runs through finer parts at higher pressure.
Myth: "If it starts and drives, there is no harm done." This is the one that catches motorists. Diesel in a petrol motor normally means a motor that will not run: the driver stops, and so does the harm. A diesel fed petrol normally starts, idles and drives away as if nothing has happened, whilst the pump wears. A running engine doesn't mean fine.
An outdated workaround for a separate fault is behind this one. Myth: "Add some two-stroke oil and drive it home." None of what petrol weakened is put back by it — and later, the tank still contains that petrol.
Myth: "Drain that tank yourself and you're sorted." Once the engine has run, some of the petrol is no longer in that tank: it is in the filter and the fuel lines, and it goes right back through your pump on the next start. Besides, petrol cleared into a can by the road is truly risky.
How does petrol in a diesel happen?
Carelessness is seldom the cause, and no one means to do it. The forecourt makes it simple: the petrol nozzle is the smaller of the two, and it slides into a diesel filler with almost no resistance, whilst a diesel nozzle generally won't go into a petrol car at all. So the error runs one way.
The moment routine stops matching the vehicle is the moment it takes place. A new vehicle, a hire car or a courtesy car. Two cars on one drive, one petrol, one diesel. Your usual forecourt, its pumps suddenly in a different order. Filling up in a hurry on the way to Stonehaven, with a train to catch. A new-to-you diesel Renault Megane, its first fuelling, and a motorist accustomed to petrol: precisely when it happens. The hand repeats what it has always done once you add rain, a phone call or a back seat full of kids.
Next time you fill up in Silverbank: preventing petrol in a diesel
- The label is what counts, so read the petrol pump rather than the colour: in the UK unleaded handles are usually green and diesel black, yet not on every forecourt.
- The first fill in a new vehicle is the time to check your filler flap — on it, or on the cap, many cars state which fuel they take.
- Good intentions do less than a sticker or a fob in a bright colour on the diesel's key when a house has one of each. So mark it.
- 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, so tuck the phone away and keep your mind on the petrol pump.
- Up to a point, a misfuel inhibitor helps: some diesels come with a filler designed to block a petrol nozzle, and add-on devices are available for the rest. Count it as a safety net, then keep checking the pump.
- Less petrol makes a weaker blend, and so stop the moment you notice — while remembering that the next step is unchanged. It's still not to crank it.
Already put petrol in a diesel in Silverbank?
Then the order of things is brief. Starting it is out, and so is turning on your ignition. Ask the attendants to help you roll it away from the pump if you are still on the forecourt, whether that's Tesco or anywhere else. Next, 0333 366 0103. We will ask what was put in, roughly how much, and if it's been run.
Corrosion and deposits are the problem with AdBlue, where petrol brings lost protection. So if it was AdBlue, say so — and read its own Silverbank page.
Silverbank petrol in a diesel jobs: why one costs more than another
Four different tasks sit behind the four scenarios above — which is why there is no honest single price. The situation itself does most of the work of moving your cost. Two things follow that: the petrol that got in as a share of what your tank takes, then the spot the car is in and whether a van can get to it safely.
Before any quote, not after, we ask three questions: your fuel that was put in, its quantity, and whether it's run. That is why. The replies change a range into a straight figure.
About Silverbank, briefly
Silverbank is a locality situated on the riverside in Aberdeenshire, with an elevation of 61 metres and a mix of detached housing. Silverbank lies near the Hill of Banchory and Lochton of Leys, and is close to Upper Lochton. Silverbank is located approximately 15.5 miles from Aberdeen, the nearest city, and is home to around 1339 residents.
Silverbank and Aberdeenshire: where our fuel drain cover reaches
Hill of Banchory, Lochton of Leys and Upper Lochton are among the locations around Silverbank that the same teams work, answering petrol in diesel calls across Silverbank's AB postcode area. The car does not need to move to us: our technicians drain on a forecourt, in a supermarket car park, in a lay-by or on your own driveway.
In Silverbank and still at the pump?
The best spot there is, then — that is where you are. Keep it turned off, and ring.