How Worried Should You Be? Petrol in a Diesel Car in Bletchingley
Unstarted? Then less worried than you probably are. Everyone in Bletchingley starts with "have I wrecked it?", and the honest answer is usually no: petrol left in the tank of a diesel remains harmless till priming, cranking or driving draws it into the system. Petrol in Diesel is who to call, with your motor kept off, so it stays that way. Below, this page sets out what petrol really does inside a diesel, how far it may have got, and how to stop it happening to you a second time.
The engine and petrol in a diesel: what goes on
On its way through a motor, diesel does two jobs. It combusts, and before it burns it lubricates. What stops the surfaces inside the high-pressure fuel pump and the injectors from wearing against each other is your diesel flowing through them — they're made to extremely fine tolerances.
Poorly at the first, not at all at the second: that is petrol. It is thinner than diesel and takes away the protection the fuel system hinges 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 reverse of what a diesel needs from its fuel. That's where the rattling comes from.
Taken together, they show the shape the issue has. It's circulation that does the damage, not contact. Any tank with petrol in it is a fuel fault. Whatever a worn pump sheds travels on, borne by your fuel, into the injectors further along, which is why a pump that has been working on that petrol is where a mechanical problem begins.
Bletchingley, petrol in a diesel: four situations, from mild to significant
Filled up, and not started: no case is better. At a forecourt, and really only there, the petrol is still limited to that tank — since anywhere else your car was driven to get to it. The job is draining and rinsing on the spot.
Started for a moment, or only your ignition on. The system has been bled, so petrol has left the tank and got to your filter and your lines. That's usually still an easy job — a drain, a flush, and your filter seen to.
Driven a couple of miles. Now the pump has spent those miles running on thinned fuel. How hard the vehicle was driven counts as much as how far, and the work takes in your tank, the fuel lines, the filter and fresh fuel through the whole circuit. On the school run to Bletchingley Village Primary School, the distance is small. Very different once more: a trip to Westminster, under 25 miles away, or some miles on the M23, under a mile from Bletchingley, where the motor kept working hard.
It protested, and only then stopped: smoke, rattling, a throttle gone soft, an idle gone ragged. The engine is telling you the fuel is no longer acting like diesel. Whether it is the verge on High Street, a lay-by or a side road, stop there and leave it. What comes first is still the fuel drain and flush, and that takes care of it, with lasting damage very rare when a car is pulled over soon.
Stories Bletchingley drivers hear about petrol in a diesel
It will not be fine. The myth: "Fill it the rest of the way with diesel and it'll be." A bigger tank of the same mix is all it gives, because topping up removes nothing. Percentage isn't how a diesel fuel system copes with petrol, however much that guidance supposes.
If anything, the reverse holds. Myth: "A current diesel can cope with a bit of petrol." Smaller parts and higher pressure are the way a newer diesel runs its fuel, and that makes the lubrication count more, not less.
Myth: "If it starts and drives, there's no harm done." This is the one that fools drivers. Feed diesel to a petrol engine and it normally won't run, and so the driver stops — and the harm stops with them. Nothing looks to have happened when a diesel fed petrol fires up, ticks over and drives away, which it usually will; meanwhile the pump wears. Fine and running aren't the same at all.
An old fix for a separate problem lies behind this one. Myth: "Add some two-stroke oil and drive it home." It does not put back what petrol has diluted, and that petrol is still in your tank later.
The next start draws petrol back round your pump from your lines and the fuel filter, where some of that ends up once the engine has been run. That is why draining your tank yourself doesn't sort it — a myth. And, a can of petrol filled by the kerbside is genuinely risky.
How does petrol in a diesel take place?
A careless moment is rarely the cause, and nobody means to do it. A diesel nozzle mostly won't go into a petrol motor, but the slimmer petrol nozzle goes into the filler of a diesel almost without resistance — so forecourts make this one mistake easy, and only in that direction.
When routine and the car stop matching, it occurs. A motor that is new to you — hired, on loan as a courtesy car, or brand new. A household with one petrol and one diesel on the driveway. A familiar forecourt with the pumps in a different order. Filling up in a rush on the way to Nutfield, with a train to catch. A new-to-you diesel Volkswagen Tiguan, its first fuelling, and a motorist accustomed to petrol: precisely when it occurs. Throw in a back seat full of children, a phone call or rain, and the hand wins.
Next time you fill up in Bletchingley: avoiding petrol in a diesel
- Green for unleaded and black for diesel is normal in the UK — yet not on every forecourt. Go by the label on the petrol pump, not the colour.
- The first fill in a strange motor is the time to check the filler flap — on it, or on the cap, many vehicles state which fuel they take.
- One of each in the home? Label the key to your diesel — a coloured fob, a sticker — since intending to remember isn't enough.
- Before the nozzle comes off the pump the first time you fuel a hired or new vehicle, say "diesel" aloud. Silly, perhaps, but it does the trick.
- Tuck the phone away. This is an easy mistake to make whilst you're thinking about something else.
- Some diesels have a filler built to reject a petrol nozzle, and devices you can add exist for motors without one. Such an inhibitor helps up to a point — as a backstop, not a reason to stop reading the petrol pump.
- As soon as you notice, stop: less petrol inside the tank makes a thinner blend. What to do next doesn't change, though — still don't start it.
Petrol already in a diesel in Bletchingley? Start here
Short and simple, then, is the order of things. Leave it unstarted, with your ignition off as well. Still at the forecourt, at Shell or anywhere else? Ask the staff to help you push the vehicle away from the pump. Next, 0333 366 0103. We'll ask what was put in, about how much, and if it's been run.
AdBlue, not petrol? Then say so. Corrosion and deposits, not lost protection, make it a different problem — Bletchingley has a page all for it.
Bletchingley petrol in a diesel jobs: why one costs more than another
An honest single quote doesn't exist here: four scenarios, four separate jobs. Mostly, your cost shifts with which one you're in. The ratio counts next, meaning how much of your tank is petrol, followed by the position of your car and whether reaching it is safe for our van.
That's why our engineers ask three questions before pricing rather than after: what went in, how much, and whether it has run. Those answers are what turn a range into one firm number.
About Bletchingley itself
Bletchingley is a small village in Surrey, situated approximately 18.5 miles south of London and near the North Downs. Bletchingley sits at an elevation of around 141 metres, with semi-detached housing being the predominant type of accommodation. Bletchingley is close to nearby places such as White Post, Brewer Street, and Nutfield, and has a population of around 865 residents.
Fuel drain cover in Bletchingley and across Surrey
Bletchingley waits in the RH postcode area, and the teams that answer petrol in diesel jobs there work the spots around it as well — White Post, Brewer Street and Nutfield among them. Our technicians drain where the car is — your own driveway, a lay-by, a supermarket car park, a forecourt — so it never needs to come to us.
Still at the pump around Bletchingley?
Then you are in the best position there is. Switched off it stays; then phone.