Petrol in a Diesel Car in The Hythe: How Worried Should You Be?
Provided it has not been started, worry far less than you probably are. Petrol resting in a diesel tank does nothing to the motor till something draws it through the system — your ignition priming the pump, your starter, or driving on its own. So the honest answer to the first query anyone in The Hythe asks, "have I wrecked it?", is normally no. Keep it that way: leave the motor off then phone Petrol in Diesel. The remainder of this page sets out what petrol really does to a diesel, how to tell how far it has got, and how to make sure it does not happen to you again.
Petrol in a diesel: what does it do to your engine?
On its way through a motor, diesel does two tasks. Oiling comes before burning; it does both. Your high-pressure pump and your injectors are built to extremely fine tolerances, and your diesel passing through them is what keeps those surfaces from wearing down against each other.
Of those two jobs, petrol manages the first poorly and the second not at all. Being less viscous than diesel, petrol strips away the lubrication 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 why you get the rattling.
Seen together, they show what shape the issue takes. The damage is done by circulation, not by contact. Any tank with petrol in it is a fuel issue. Once your pump has been working on that petrol, a mechanical fault has begun: whatever is shed by a pump that is wearing travels downstream to the fuel injectors with the fuel.
Four situations we see around The Hythe: how serious is petrol in a diesel?
Fuelled but not once started — the best it gets. Being on a forecourt is what makes this possible: elsewhere, the vehicle has been driven there to begin with. With that petrol kept inside the tank alone, it's cleared and purged right where it stands, and nothing more is needed.
Started for a moment, or only your ignition on. The system has been bled, and so petrol has left that tank and got to your filter and your lines. Drain, flush, deal with the fuel filter: still normally straightforward.
Driven a few miles. Now the pump has spent these miles working on weakened fuel. The work is the tank, the fuel lines, your filter and clean fuel through the whole circuit, and how hard your car was driven counts as much as how far. A school run to Kendall Church of England Primary School is one thing. Very different once more: a trip to Colchester, under 3 miles away, or some miles on the M11, under 50 miles from The Hythe, where the engine kept running hard.
It protested, and only then stopped: smoke, rattling, a throttle gone soft, an idle gone uneven. The fuel isn't acting like diesel any more, and the motor is telling you. Leave it wherever it stops: a lay-by, a side street, the verge on Haven Road. A vehicle pulled over early very rarely has long-term damage, as the drain and the flush-through, which still come first, deal with it.
What The Hythe motorists get told about petrol in a diesel — and the myths in it
False: topping up to full with diesel makes it fine. It doesn't. Topping up removes nothing; it gives you a bigger tank of the same mix. The idea behind that guidance — that diesel fuel systems accept petrol by percentage — is wrong.
"Newer diesels can handle a little petrol" — a myth, and closer to the reverse. At higher pressure, through finer components: that's how a current diesel handles its fuel, so the lubrication counts more, not less.
This is the one that fools motorists. Myth: "If it starts and drives, there's no harm done." Diesel in a petrol motor usually means a motor that will not run: the motorist stops, and so does the harm. Whilst your pump grinds, a diesel fed petrol normally starts, ticks over and drives away as though nothing has happened. Running isn't the same as fine.
Myth: "Add some two-stroke oil and drive the vehicle home." It is an outdated workaround for a distinct issue. None of what petrol weakened is put back by it — and later, the tank still contains the petrol.
Myth: "Drain that tank yourself and you are sorted." Once the engine has been run, some of that petrol is no longer inside the tank: it is in your filter and your lines, and it goes right back through your pump at the next start. Emptying petrol into a can by the roadside is also really dangerous.
How does petrol in a diesel take place?
On purpose? Never. Through carelessness? Rarely, if ever. A diesel nozzle mostly won't go into a petrol vehicle, yet the smaller petrol nozzle goes into the filler of a diesel nearly without resistance — so forecourts make this one mistake simple, and only in that direction.
Habit and your car falling out of step is how it takes place. Courtesy car, hire car, or a motor that's new. A household with one petrol and one diesel on the drive. The pumps in a different order on a familiar forecourt. Racing for a train outside Hythe and filling up en route. A new-to-you diesel Volkswagen Passat, its first fuelling, and a driver used to petrol: precisely when it happens. Add rain, a phone call or a back seat full of kids, and your hand does what it has always done.
Next time you fill up in The Hythe: preventing petrol in a diesel
- The label is what matters, and so read the pump instead of the colour: in the UK unleaded handles are usually green and diesel black, but not on every forecourt.
- Inspect the filler flap. Many cars state the fuel inside the flap or on the cap. Look at it on the first fill in a motor you don't know.
- A coloured fob or a sticker on your diesel's key achieves more than any amount of intending to remember, for a house with one of each.
- It seems silly and it works: on the first fill in a new or hired car, say "diesel" aloud before you lift the nozzle off the petrol pump.
- Tuck your phone away. This is an easy mistake to make whilst you're thinking about something else.
- Up to a point, a misfuel inhibitor helps: some diesels have a filler built to reject a petrol nozzle, and add-on devices are available for the rest. Count it as a safety net, and keep reading the pump.
- Noticing it mid-fill? Stop there and then. A weaker mix follows from less petrol in that tank, yet your next stage remains the same: don't crank it.
Already put petrol in a diesel in The Hythe?
Short and simple, then, is the order of things. Don't crank it, and don't switch the ignition on. If you are still at the forecourt — Tesco or anywhere else — ask the staff to help you roll the car away from the pump. Then phone 0333 366 0103 and tell us what was put in, roughly how much, and if it's run.
Say so if it was AdBlue instead of petrol: it's a separate fault, with its own page for The Hythe, since AdBlue brings corrosion and deposits rather than lost protection.
Why one petrol in a diesel job in The Hythe costs more than another
The four situations above are four different jobs, so no single quote for this would be honest. What shifts the cost is chiefly which of them you are in. Beyond that it's the share — how much petrol went in against how much the tank holds — and then where your car is and whether a technician can get to it safely.
What got in, how much, and if it's run — three questions we ask before costing, not after, for precisely that reason. Those answers are what change a range into one firm number.
About The Hythe and its setting
The Hythe is a suburban area located on the River Colne in Essex, with a mix of residential and industrial development. The Hythe sits at a low elevation of around 6 metres, close to the city of Colchester and near other local areas such as Old Heath and Greenstead. The Hythe is characterized by its predominantly flat housing stock, with many residents enjoying views of the river. The Hythe is also relatively distant from London, at around 52 miles away.
Across Essex and in The Hythe: fuel drain cover
Petrol in diesel call-outs in The Hythe — part of the CO postcode area — go to teams that also cover the places round it, Old Heath, Greenstead and Abbey Field among them. You need not bring your car to us. Forecourts, supermarket car parks, lay-bys and your own driveway are all locations where we work.
At the petrol pump around The Hythe, right now?
Then you're in the best spot there can be. Leave it switched off, and ring.