How Worried Should You Be? Petrol in a Diesel Car in Stedham
Provided it hasn't been started, you can worry less than you probably are. "Have I wrecked it?" is the first question anyone around Stedham asks, and the truthful answer is generally no, since petrol resting in a diesel tank hurts nothing till it is drawn through your fuel system — by ignition priming, by your starter, or by being driven. To leave it like that, call Petrol in Diesel and leave the engine alone. Keep reading for three things: the effect petrol has inside a diesel motor, the clues of how far it has got, and ways to make sure you never repeat it.
Petrol in a diesel: what does it do to the engine?
Diesel has two jobs on its way through a motor. It protects to begin with, and after that does it burn. The high-pressure fuel pump and the fuel injectors are designed to very fine gaps, and the diesel passing through them is what keeps those surfaces from wearing down against one another.
Petrol handles the first job badly and the second not at all. It's runnier than diesel and strips away the lubrication your fuel system rests on, and so a pump running on a petrol mixture is a pump wearing itself. And petrol is designed to resist igniting under compression, which is the opposite of what a diesel needs from its fuel. That's where the clattering comes from.
The shape of the trouble is plain when you put those together. Not contact but circulation is what does the harm. All a tank with petrol in it amounts to is a fuel issue. Once your pump has been labouring on that petrol, a mechanical issue has started: whatever is shed by a pump that's wearing travels onward to your injectors with the fuel.
Four scenarios our engineers see in Stedham: how bad is petrol in a diesel?
Filled up, and never started: no case is better. Being on a forecourt is what makes this the case: elsewhere, the car has been driven there to begin with. With that petrol kept in your tank alone, it is drained and rinsed on the spot, and nothing more is needed.
Started for a second, or just your ignition on. Once primed, the fuel system has pulled petrol out of that tank up to your filter and the fuel lines. That's usually still a straightforward job — a drain, a flush, and your filter dealt with.
The pump has spent a couple of miles on diluted fuel — that's what driving it does. The work is that tank, the lines, the filter and fresh fuel through the entire circuit, and how hard the car was driven counts as much as how far. On the school run to Stedham Primary School, the miles is short. Any distance on the Waterlooville Bypass, under 15 miles from Stedham, means the engine working hard throughout, and a run to Chichester, under 15 miles away, makes a very different job too.
It complained, and only then stopped: smoke, knocking, a throttle gone soft, an idle gone ragged. The fuel is not acting like diesel any more, and the motor is telling you. Pull up where you are — on the verge on The Street, at the kerb, down a side road — and do not move it. Permanent damage is very uncommon if a car is stopped quickly, and the fuel drain and flush-through that still come first sort it out.
What Stedham drivers get told about petrol in a diesel — and the myths in it
It will not be fine. The myth: "Fill it the rest of the way with diesel and it will be." Nothing comes out when you top up — your tank simply carries more of the same blend. A diesel fuel system does not tolerate petrol by percentage in the way that advice assumes.
"Modern diesels can handle a little petrol" — a myth, and nearer the opposite. At higher pressure, through more precise components: that is how a modern diesel handles its fuel, and so the protection matters more, not less.
This is the one that fools people. Myth: "If it starts and drives, there's no harm done." Any petrol motor fed diesel usually will not run, so the driver stops and the damage stops with them. A diesel fed petrol generally starts, ticks over and drives away as if nothing has happened, while your pump grinds. Running doesn't mean fine.
Myth: "Add some two-stroke oil and drive the vehicle home." It is an old fix for a different problem. It doesn't put back what petrol has thinned, and the petrol is still inside that tank later on.
If your engine has run, part of the petrol is in the fuel filter and your lines, not the tank — and your next start sends it straight back through your pump. So the myth "drain the tank yourself and you are sorted" does not hold. Emptying petrol into a can at the roadside is also truly risky.
Petrol in a diesel: how does it occur?
On purpose? Never. Through carelessness? Seldom, if ever. The petrol nozzle is the slimmer of the two and slips 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 mistake runs one way.
When routine and the vehicle stop matching, it happens. A new car, a hire car or a courtesy car. Households running one of each, petrol and diesel. A forecourt you know, but with its pumps arranged differently. Rushing for a train outside Liphook and fuelling up en route. The first fill-up in a diesel Renault Clio after years of driving petrol is precisely the moment it happens. The hand does what it has always done when you add rain, a phone call or a back seat full of kids.
Avoiding petrol in a diesel next time you fill up around Stedham
- Read the petrol pump, not the colour. In the UK unleaded handles are generally green and diesel black, but not on each forecourt. The label is what matters.
- The first fill in a new vehicle is the time to check your filler flap — on it, or on the cap, many motors state the fuel to use.
- One of each in the household? Label the key to the diesel — a coloured fob, a sticker — since meaning to remember is not enough.
- Before the nozzle comes off the pump the first time you fuel a hired or new vehicle, say "diesel" out loud. Daft, yes, but it does the trick.
- Mistakes like this are straightforward to make whilst your mind is on something else, so the phone goes away.
- Some diesels have a filler built to refuse a petrol nozzle, and devices you can add are available for vehicles without one. Such an inhibitor helps up to a point — as a safety net, not a reason to stop checking the petrol pump.
- Noticing it halfway? Stop at once. A weaker mixture follows from less petrol in that tank, but the next step stays the same: don't start the vehicle.
Already put petrol in a diesel in Stedham?
Then the order of things is brief. Starting it is out, and so is turning on the ignition. If you're still at the forecourt — Trotton Gate Garage or anywhere else — ask the staff to help you push the car away from the petrol pump. What got in, roughly how much, and if it has run: tell us those when you phone 0333 366 0103.
Say so if it was AdBlue instead of petrol: it is a different problem, with its own page for Stedham, because AdBlue brings corrosion and deposits instead of lost lubrication.
What makes one Stedham petrol in a diesel job cost more than the next
There's no honest single quote for this, because the four situations above are four different tasks. What shifts the cost is mostly which of them you're in. Where your car is matters too, and whether a van can safely reach it, after the share of petrol to what that tank holds.
What went in, how much, and if it has run — three questions we ask before quoting, not after, for exactly that reason. Given those replies, you get a straight figure rather than a range.
About Stedham, for a moment
Stedham is a village situated on the River Rother in West Sussex, with a low elevation of around 37 metres above sea level. Stedham lies near the South Downs National Park and is close to nearby places such as Quags Corner, Minsted, and Iping. Stedham has a population of approximately 561 people and predominantly consists of semi-detached housing. Stedham is located near the city of Chichester, which is about 10.8 miles away, and is around 45.2 miles from London.
Stedham and West Sussex: where our fuel drain cover reaches
Stedham waits in the GU postcode area, and the teams that answer petrol in diesel call-outs there work the locations around it as well — Quags Corner, Minsted and Iping among them. A forecourt, a supermarket car park, a lay-by or your own driveway are all spots our technicians work, and your vehicle does not need to move to us.
Stedham: still at the pump?
The best spot there is, then — that's where you are. Ring, and leave it switched off.