Should You Worry? Petrol in a Diesel Car in Aarons Hill
Far less than you likely are, provided it has not been started. Everyone around Aarons Hill begins with "have I wrecked it?", and the fair answer is generally no: petrol left inside that tank of a diesel stays harmless until priming, cranking or driving pulls it into the system. Leave your engine off then phone Petrol in Diesel — that is how you keep it like that. What petrol really does to a diesel, how to judge how far it has gone, and how to stop it from happening again: that's the remainder of this page.
Inside the motor: what petrol in a diesel does
Diesel does two tasks on its way through a motor. Oiling comes before burning; it does both. Extremely fine clearances go into the injectors and your high-pressure pump, and just your diesel flowing through keeps their surfaces from grinding together.
Of those two tasks, petrol handles the first poorly and the second never. It is thinner than diesel and strips away the lubrication the fuel system rests on, 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 reverse of what a diesel needs from its fuel. That is where the knocking comes from.
Together, those make the shape of the issue plain. Contact doesn't do the damage — movement does. Any tank with petrol in it is a fuel fault. The start of a mechanical problem is a pump that has been labouring on that petrol — and whatever a worn pump sheds moves on with your fuel to the fuel injectors beyond it.
Four situations our technicians see in Aarons Hill: how serious is petrol in a diesel?
Fuelled but never started — the best it gets. On a forecourt, and genuinely only there, that petrol is still limited to the tank — since anywhere else the car was driven to get to it. The job is emptying and cleaning on the spot.
The ignition switched on, or a brief start. Petrol has left that tank and reached the fuel filter and the fuel lines, because your system has been primed. Drain, flush, see to the filter: still usually straightforward.
Your pump has spent a few miles on thinned fuel — that is what driving the vehicle does. Mileage is only half of that; how hard it was driven matters just as much. Either way the work runs to that tank, the lines, the filter and fresh fuel through the entire system. Short trips, such as the school run to St Mark and All Saints Church of England Primary, are one matter. Very different a second time: a run to Chichester, under 25 miles away, or some miles on the M3, under 15 miles from Aarons Hill, where your engine kept working hard.
Driven till it complained. Rattling, an uneven idle, smoke, a throttle that has gone soft. The motor is telling you the fuel is no longer acting like diesel. Leave it wherever it stops: a lay-by, a quiet street, the verge on Aarons Hill. A car stopped quickly very seldom has lasting damage, as the fuel drain and the flush-through, which still go first, take care of it.
Petrol in a diesel stories Aarons Hill people hear
Myth: topping up to full with diesel makes it fine. It does not. Topping up takes out nothing; it gives you a bigger tank of the same mix. That advice supposes a diesel fuel system tolerates petrol by percentage. It does not.
Myth: a newer diesel copes with a bit of petrol. If anything, the opposite. A modern diesel runs its fuel through smaller components at higher pressure, which makes the protection count more, not less.
This is the one that catches motorists. Myth: "If it starts and drives, there's no damage done." A petrol engine fed diesel normally will not run, so the driver stops and the harm stops with them. A diesel fed petrol usually starts, idles and drives away as though nothing has happened, whilst your pump grinds. A running engine does not mean fine.
Myth: "Add some two-stroke oil and drive the car home." It is an old fix for a different problem. That petrol is still in that tank afterwards, and what it has thinned is not put back.
"Drain it yourself and you're sorted" — a myth, since after it's been running some petrol lies in your filter and lines, ready to go straight back through your pump at your next start. On top of that, petrol drained into a can by the road is genuinely dangerous.
How does petrol in a diesel happen?
On purpose? Never. Through carelessness? Rarely, if ever. The petrol nozzle is the smaller of the two and slips into a diesel filler with almost no resistance; a diesel nozzle generally will not go into a petrol vehicle at all. The forecourt makes it simple, and the error runs one way.
It occurs when routine and your car stop matching. Any vehicle that's new to you — hired, on loan as a courtesy car, or just bought. One petrol and one diesel on the driveway of the same household. A forecourt you know, but with its pumps arranged differently. A hurried fill on the way to Godalming with a train to catch. A new-to-you diesel Volkswagen Golf, its first fuelling, and a driver used to petrol: exactly when it occurs. The hand repeats what it has always done when you add rain, a phone call or a back seat full of children.
How to avoid petrol in a diesel on your next fill-up in Aarons Hill
- The label is what matters, so read the pump instead of the colour: in the UK unleaded handles are normally green and diesel black, but not on every forecourt.
- Many cars state the fuel inside your filler flap or on the cap, and so check it on the first fill in any motor you do not know.
- Mark 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 sounds silly and it does the trick: on your 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 whilst you're thinking about something else.
- Add-on devices are available for motors without one, and some diesels are built with a filler that won't take a petrol nozzle. Useful — but a backstop only, never a reason to stop checking the label.
- Spotting it halfway? Stop at once. A thinner mixture follows from less petrol inside that tank, but your next stage remains the same: don't fire it up.
Petrol already in a diesel in Aarons Hill? Start here
Then, there's just a short order of things. Never start it, and don't turn your ignition on. Still at the forecourt, at JET or anywhere else? Ask the attendants to help you push it clear of the petrol pump. Next, 0333 366 0103. We'll ask what went in, roughly how much, and if it's been run.
AdBlue, not petrol? Then say so. Corrosion and deposits, not lost protection, make it a separate issue — Aarons Hill has a page all for it.
One petrol in a diesel job in Aarons Hill costs more than another. Why?
There is no honest single price for this, since the four scenarios above are four separate jobs. The situation itself does most of the work of moving your cost. Where the car is counts too, and whether a technician can safely get to it, after the ratio of petrol to what that tank takes.
Three questions come first, before any quote, instead of after — what was put in, how much, has it run — and this is the reason. With the answers, there is a straight figure rather than a range.
About Aarons Hill itself
Aarons Hill is a suburban area in Surrey, situated near the riverside with an elevation of 78 metres. Aarons Hill lies within the South East region of England, approximately 31 miles from London. Aarons Hill is surrounded by nearby places such as Ockford Ridge, Westbrook, and Upper Eashing, and is characterized by predominantly semi-detached housing. Aarons Hill has a population of around 1937 residents.
Fuel drain cover around Aarons Hill and across Surrey
Aarons Hill sits in the GU postcode area, and our vans that answer petrol in diesel jobs there work the locations near it as well — Ockford Ridge, Westbrook and Upper Eashing among them. A forecourt, a supermarket car park, a lay-by or your own drive are all places our engineers work, and the vehicle does not need to come to us.
Aarons Hill: still at the petrol pump?
Then you're in the best position there is. Call, and keep it switched off.