Kineton Green: Petrol in a Diesel Car? How Worried to Be
Not started? Then less worried than you likely feel. Petrol sitting in a diesel tank does nothing to your engine till something draws it through the fuel system — your ignition priming the pump, the starter, or driving itself. So the honest answer to the first question anyone in Kineton Green asks, "have I ruined it?", is generally no. Leave the motor off then call Petrol in Diesel — that keeps it like that. What petrol really does to a diesel, how to gauge how far it has travelled, and how to keep it from happening again: that's the rest of this page.
Your engine and petrol in a diesel: what happens
Passing through a motor, diesel is doing two things at the same time. It protects first, and only then does it burn. What keeps the surfaces inside the high-pressure fuel pump and the injectors from wearing against each other is your diesel flowing through them — they are designed to very fine tolerances.
Petrol handles the first task badly and the second not at all. Being less viscous than diesel, petrol strips out the protection a fuel system needs, leaving a pump 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 hear the knocking.
The shape of the problem is plain when you put those together. The damage is done by circulation, not by contact. Where the petrol is only in your tank, it is a fault of fuel, nothing more. The start of a mechanical problem is a pump that has been working on that petrol — and whatever a worn pump sheds travels on with the fuel to the injectors beyond it.
Four situations our technicians see in Kineton Green: how serious is petrol in a diesel?
Fuelled but never started — the best it gets. Only your tank has petrol in it, so the job is clearing the tank and cleaning your system where the car stands. This situation can only really take place on a forecourt: anywhere else, the car got there by being driven.
Ignition on, or started for a second. With the fuel system primed, the lines and filter now hold petrol that came from your tank. That's generally still a simple job — a drain, a flush, and the filter dealt with.
Driven a couple of miles. Now your pump has spent those miles working on diluted fuel. Distance is only half of it; how hard it was driven counts equally. Either way the work includes the tank, your lines, your filter and fresh fuel through the whole circuit. Driving the kids to Our Lady of Compassion Catholic Primary School is one kind of trip. A run as far as Birmingham, under 10 miles away, is a very different task. So is any distance on the M42, under 3 miles from Kineton Green, where the engine has been working hard throughout.
Driven until it complained. Clattering, a ragged idle, smoke, a throttle that has gone soft. That is your engine telling you its fuel no longer is behaving like diesel. Whether it is the verge on St Bernards Road, a lay-by or a side road, stop there then leave it. The drain and flush still come first, and they sort it out: when a car is pulled over soon, lasting damage is very uncommon.
Stories Kineton Green people hear about petrol in a diesel
Myth: "Fill it the rest of the way with diesel and it'll be fine." It will not. A fuller tank of the same mixture is all it gives, since topping up takes out nothing. 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 smaller parts: that is how a modern diesel handles its fuel, so the lubrication counts for more, not less.
"It starts, it drives, so there is no harm" — the myth that catches more motorists than any other. Diesel in a petrol motor normally means a motor that will not run: the driver stops, and so does the harm. Nothing seems to have happened when a diesel fed petrol fires up, ticks over and drives away, which it usually will; meanwhile the pump grinds. Running is not the same as fine.
Myth: "Add some two-stroke oil and drive it home." It is an old fix for a distinct issue. It does not put back what petrol has diluted, and that petrol is still in the tank after that.
"Drain it yourself and you are sorted" — a myth, because after it has been running some petrol lies in the fuel filter and lines, ready to go straight back through your pump at the next start. It's also really dangerous to drain petrol into a can at the roadside.
How it happens: petrol in a diesel
It's rarely carelessness, and no one does it on purpose. One way only, since of the nozzles: the slimmer petrol one slides inside a diesel filler with almost no resistance, whereas the diesel one mostly won't fit a petrol motor. That's how the forecourt makes it straightforward.
It happens when habit and your car stop matching. Hire cars, courtesy cars, and vehicles that are new to you. A household with one petrol and one diesel on the driveway. A forecourt you know, only with its pumps laid out differently. Racing for a train outside Olton and filling up en route. A new-to-you diesel Volkswagen Passat, its first fuelling, and a motorist accustomed to petrol: precisely when it takes place. Add rain, a phone call or a back seat full of children, and your hand repeats what it has always done.
Next time you fill up around Kineton Green: preventing petrol in a diesel
- Green for unleaded and black for diesel is normal in the UK — yet not on every forecourt. Trust the label on the petrol pump, not the colour.
- Inspect your filler flap. Many cars state the fuel inside the flap or on the cap. Look at it on your first fill in any vehicle you don't know.
- One of each in the household? Mark the key to the diesel — a coloured fob, a sticker — because intending to remember is not enough.
- "Diesel", out loud, before you pick up the nozzle — each time a new or hired car gets its first tank. It seems silly. It works.
- While you're thinking about something else, this is an easy mistake to make — so tuck the phone away.
- Add-on devices exist for vehicles without one, and some diesels come with a filler that won't take a petrol nozzle. Useful — but a backstop at best, never a reason to stop checking the label.
- Less petrol makes a weaker mix, so stop the moment you notice — while remembering that the next stage is unchanged. It is still not to fire it up.
Petrol already in a diesel in Kineton Green? Start here
Then the order of things is brief. Do not start the car, and do not turn your ignition on. The attendants on the forecourt — whether at BP itself or wherever you filled up — will usually help roll it away from the pump if you ask. Ring 0333 366 0103 next, with three facts — your fuel, the rough quantity, and if it's run.
Corrosion and deposits are the trouble with AdBlue, whereas petrol brings lost lubrication. So if it was AdBlue, say so — and read its own Kineton Green page.
Kineton Green petrol in a diesel tasks: why one costs more than another
A fair single price doesn't exist here: four situations, four separate tasks. The situation itself does most of the work of moving the cost. Where the car is counts too, and whether a van can safely get to it, after the proportion of petrol to what that tank takes.
That is why our engineers ask three questions before quoting rather than after: what got in, how much, and whether it's run. A range turns into a straight figure once those answers are in.
About Kineton Green itself
Kineton Green is a suburban area located near the lakes in the West Midlands, with a mix of housing types but predominantly detached homes. Kineton Green sits at an elevation of 135 metres, close to the city of Birmingham and near other suburban areas like Ulverley Green and Shirley. Kineton Green is part of the larger Birmingham urban area, with the city centre just 5.2 miles away. Kineton Green has a population of around 4458 residents.
Fuel drain cover in Kineton Green and across West Midlands
Petrol in diesel calls around Kineton Green — part of the B postcode area — go to teams that also cover the spots around it, Ulverley Green, Shirley and Hall Green included. The vehicle does not need to come to us: we drain on a forecourt, in a supermarket car park, in a lay-by or on your own driveway.
In Kineton Green and still at the petrol pump?
No position is better: that is where you are. Keep the vehicle turned off, and ring.