Balladen: Petrol in a Diesel Car? How Worried to Be
Not started? Then less worried than you likely feel. Everyone in Balladen begins with "have I ruined it?", and the honest answer is normally no: petrol left inside the tank of any diesel remains harmless until priming, cranking or driving draws it into your fuel system. To keep the car like that, ring Petrol in Diesel and leave your motor alone. The rest of this page covers what petrol really does to a diesel, how to judge how far it has got, and how to make sure it does not happen to you a second time.
Your engine and petrol in a diesel: what happens
Diesel does two jobs on its way through an engine. It ignites, and before it combusts it protects. Built to very fine clearances, your injectors and your pump depend on your diesel moving through them to stop their surfaces wearing against one another.
Of those two jobs, petrol handles the first poorly and the second not at all. Being less viscous than diesel, petrol strips out the lubrication a fuel system needs, so a pump running on the blend wearing itself. It's equally made to resist igniting under compression — the reverse of what a diesel needs — which is why you get the knocking.
Combined, those make the shape of the problem plain. The damage is done by circulation, not by contact. All a tank with petrol in it amounts to is a fuel problem. Whatever a worn pump sheds travels on, borne by the fuel, into the injectors downstream, which is why a pump that has been working on that petrol is where a mechanical problem starts.
How serious is petrol in a diesel? Four situations our engineers see around Balladen
Fuelled up, not once started. The best case there is. Being on a forecourt is what makes this possible: elsewhere, the car has been driven there to begin with. With the petrol kept in your tank alone, it's cleared and rinsed right where it stands, and nothing more is needed.
The ignition switched on, or a short start. Petrol has come out of that tank and reached the filter and your lines, because the fuel system has been primed. Still generally easy: drain, flush, and the filter dealt with.
Those few miles on the road were the pump labouring on fuel weakened by petrol throughout. Miles is only half of it; how hard it was driven counts equally. Either way the work includes the tank, your lines, the fuel filter and clean fuel through the entire system. Short trips, such as the school run to Rawtenstall Balladen Community Primary School, are one matter. Any distance on the M66, under 3 miles from Balladen, means the engine has worked hard throughout, and a run to Salford, under 15 miles away, makes a very different job too.
Driven until it complained. Knocking, an uneven idle, smoke, a throttle that has gone soft. That is your motor telling you its fuel has stopped behaving like diesel. Pull up wherever you are — the verge on Horncliffe Close, a lay-by, a side street — then leave the car where it is. Long-term damage is very rare if a vehicle is pulled over quickly, and the drain and flush-through that still go first sort it out.
Petrol in a diesel stories Balladen motorists hear
Myth: topping up to full with diesel makes it fine. It does not. Nothing is removed when you top up — the tank just carries more of the same blend. The idea behind that advice — that diesel fuel systems tolerate petrol by percentage — is wrong.
If anything, the opposite holds. Myth: "A current diesel can cope with a bit of petrol." A newer diesel sends its fuel through more precise components at higher pressure, which makes the lubrication matter more, not less.
Myth: "If it starts and drives, there is no harm done." This is the one that catches drivers. Any petrol engine fed diesel generally won't run, so the motorist stops and the harm stops with them. Whilst the pump wears, a diesel fed petrol normally starts, idles and drives away as though nothing has happened. Running is not the same as fine.
"A drop of two-stroke oil and drive it home" — a myth, borrowed from a fix from years ago, for a separate fault. None of what petrol thinned is put back by it — and later, the tank still holds that petrol.
Myth: "Drain that tank yourself and you are sorted." After the motor has run, some of the petrol is no longer in that tank: it's in your filter and your lines, and it goes straight back through the pump on the next start. Emptying petrol into a can by the roadside is also genuinely dangerous.
How it happens: petrol in a diesel
A careless moment is rarely the cause, and no one means to do it. A diesel nozzle generally won't fit a petrol motor, but the slimmer petrol nozzle goes into the filler of a diesel nearly without resistance — so forecourts make this one mistake simple, and only in that direction.
The moment habit stops matching the vehicle is the moment it takes place. A new vehicle, a hire car or a courtesy car. A household with one petrol and one diesel on the drive. Your usual forecourt, its pumps suddenly in a different order. Rushing for a train at Accrington and filling up en route. The first fill-up in a diesel Volkswagen Golf after years of driving petrol is exactly the moment it takes place. Your hand repeats what it has always done once you add rain, a phone call or a back seat full of kids.
How to prevent petrol in a diesel at your next fill-up in Balladen
- The label is what matters, so check the petrol pump rather than the colour: in the UK unleaded handles are normally green and diesel black, but not on every forecourt.
- In a motor you don't know, look inside the flap over the filler or at the cap before the first fill: plenty of motors state the fuel there.
- Label the key. In a house with one of each, a coloured fob or a sticker on your diesel's key does more than any amount of intending to remember.
- It seems silly and it does the trick: on the first fill in a new or hired car, say "diesel" aloud before you lift the nozzle off the petrol pump.
- Tuck the phone away. This is an easy mistake to make while you're thinking about something else.
- A misfuel inhibitor helps, up to a point. Some diesels have a filler built to block a petrol nozzle, and add-on devices exist for cars without one. They are a backstop, not a reason to stop reading the pump.
- Spotting it halfway? Stop there and then. A thinner mix results from less petrol inside your tank, yet the next stage stays the same: don't fire it up.
Balladen: already put petrol in a diesel?
The order of things is short, then. Leave it unstarted, with your ignition switched off too. The attendants on the forecourt — whether at Tesco itself or wherever you filled up — will usually help roll it clear of the petrol pump if you ask. Then ring 0333 366 0103 and tell us what was put in, roughly how much, and whether it has run.
Corrosion and deposits form the trouble with AdBlue, where petrol means lost protection. So if it was AdBlue, say so — and read its own Balladen page.
One petrol in a diesel job around Balladen costs more than another. Why?
Four different tasks sit behind the four situations above — which is why there is no honest single price. What shifts the cost is mostly which of them you are in. Two things come after that: the petrol that went in as a proportion of what that tank holds, then the spot the car is in and whether a van can get to it safely.
What got in, how much, and if it has run — three questions our technicians ask before costing, not after, for precisely that reason. Those answers turn a range into a straight figure.
About Balladen, briefly
Balladen is a locality in Lancashire, situated on the riverside at an elevation of 225 metres, with detached housing being the predominant type of accommodation. Balladen lies near several other small places, including Townsend Fold, Wood Top, and Hall Carr, and is approximately 14.4 miles from the city of Salford. Balladen is characterized by its rural setting and relatively small population of around 968 residents. Balladen is also some distance from the capital, being around 176.1 miles from London.
Fuel drain cover around Balladen and across Lancashire
Petrol in diesel calls around Balladen — part of the BB postcode area — go to teams that also cover the spots around it, Townsend Fold, Wood Top and Hall Carr included. A forecourt, a supermarket car park, a lay-by or your own drive are all places we work, and the vehicle does not need to come to us.
At the pump around Balladen, right now?
The best position there is, then — that is where you are. Switched off it remains; then call.