Petrol in a Diesel Car in Tettenhall Wood: How Worried Should You Be?
If it hasn't been started, worry far less than you probably are. Everyone around Tettenhall Wood begins with "have I ruined it?", and the fair answer is usually no: petrol left inside the tank of any diesel remains harmless until priming, cranking or driving draws it into your fuel system. Petrol in Diesel is who to phone, with the engine left off, so it stays that way. The remainder of this page explains what petrol actually does to a diesel, how to judge how far it has got, and how to make sure it doesn't happen to you again.
Petrol in a diesel: what does it do to the motor?
Two tasks fall to diesel on its journey through a motor. It lubricates to begin with, and only then does it burn. The high-pressure pump and the injectors are built to very fine tolerances, and the diesel passing through them is what keeps those surfaces from wearing against each other.
Of these two jobs, petrol handles the first badly and the second not at all. A pump running on a petrol mixture is wearing itself out, since petrol is runnier than diesel and takes away the lubrication your fuel system relies on. Petrol is also made to resist igniting under compression — the reverse of what a diesel needs from its fuel — and that is where the knocking comes.
Combined, those leave the shape of the problem clear. Not contact but circulation is what does the harm. All a tank with petrol in it amounts to is a fuel fault. After your pump has been labouring on that petrol, a mechanical issue has begun: anything shed by a pump that's grinding is carried onward to your injectors with your fuel.
Tettenhall Wood, petrol in a diesel: four cases, from mild to significant
Fuelled but never started — as good as it gets. Being at a forecourt is what makes this possible: elsewhere, the car has been driven there to begin with. With the petrol kept inside your tank alone, it is drained and purged on the spot, and nothing more is needed.
Ignition on, or started for a second. Petrol has left your tank and got to the filter and the fuel lines, because the fuel system has been bled. That is generally still an easy task — a drain, a flush, and the fuel filter seen to.
Driven a couple of miles. Now your pump has spent those miles running on thinned fuel. Miles is only half of it; how hard it was driven matters equally. Either way the work runs to the tank, the fuel lines, the filter and fresh fuel through the whole system. On the school run to Christ Church (Church of England) Infant and Nursery School, the miles is short. Driving as far as Wolverhampton, under 3 miles away, makes a very different job — as does any miles on the M54, under 5 miles from Tettenhall Wood, with your engine working hard the whole time.
It complained, and only then stopped: smoke, rattling, a throttle gone soft, an idle gone lumpy. The fuel is not behaving like diesel any more, and your engine is saying so. Stop where you are — on the verge on Church Road, at the kerb, down a side road — and do not move it again. What comes first is still the drain and flush, and that sorts it out, with permanent damage very rare if a vehicle is pulled over quickly.
Petrol in a diesel stories Tettenhall Wood motorists hear
"Top it up the rest of the way with diesel and it'll be fine" — a myth. It will not. Nothing is removed when you top up — the tank just holds more of the same mixture. Percentage isn't how a diesel fuel system tolerates petrol, whatever that advice assumes.
"Newer diesels can handle a little petrol" — a myth, and closer to the reverse. At higher pressure, through finer components: that's how a newer diesel moves its fuel, so the protection counts for more, not less.
The myth that catches motorists off guard: if it starts and drives, it must be unharmed. Diesel in a petrol motor normally means a motor that will not run: the driver stops, and so does the harm. Feed petrol to a diesel and it generally fires up, ticks over and drives away as if nothing has happened — all while its pump is wearing. A running engine doesn't mean fine.
"A drop of two-stroke oil and drive it home" — a myth, taken from a fix from years ago, for a different fault. The petrol is still inside that tank after that, and whatever it has weakened is not put back.
"Drain it yourself and you are sorted" — a myth, because after it has been running some petrol lies in the fuel filter and lines, waiting to go straight back through your pump on the next start. It's also really hazardous to drain petrol into a can at the roadside.
How it happens: petrol in a diesel
It's rarely carelessness, and nobody does it on purpose. One way only, since of the nozzles: the slimmer petrol one slips inside a diesel filler with almost no resistance, while the diesel one generally won't fit a petrol car. That is how the forecourt makes it simple.
Habit and the vehicle getting out of step is how it occurs. Hire cars, courtesy cars, and vehicles that are new to you. A household with one petrol and one diesel on the drive. Your usual forecourt, its pumps suddenly in a different order. A hurried fill en route to Bilbrook with a train to catch. A new-to-you diesel Nissan Qashqai, its first fuelling, and a driver accustomed to petrol: precisely when it happens. Throw in rain, a phone call or a back seat full of kids, and the hand repeats what it has always done.
How to prevent petrol in a diesel on your next fill-up around Tettenhall Wood
- Not every forecourt in the UK keeps to green for unleaded and black for diesel, though most usually do. Read the pump's label; the colour is only a clue.
- In a motor you don't know, look inside the flap over the filler or at the cap before your first fill: plenty of motors print the fuel there.
- A coloured fob or a sticker on the diesel's key does more than any amount of intending to remember, in a house with one of each.
- It seems daft and it does the trick: on the first fill in a new or hired car, say "diesel" out loud before you lift the nozzle off the 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 designed to reject a petrol nozzle, and add-on devices are available for the rest. Count it as a safety net, then keep reading the pump.
- Spotting it halfway? Stop at once. A thinner blend results from less petrol inside the tank, yet the next step remains the same: don't start the car.
Put petrol in a diesel in Tettenhall Wood already?
The order of things is short, then. Don't switch the ignition on, and don't fire it up. The staff on the forecourt — whether at Shell itself or wherever you filled up — will normally help roll it clear of the pump if you ask. Next, 0333 366 0103. We'll ask what went in, roughly how much, and if it's been run.
If it was AdBlue rather than petrol, say so. That's a separate issue — corrosion and deposits rather than lost protection — and it has its own page for Tettenhall Wood.
Why one petrol in a diesel job in Tettenhall Wood costs more than another
Four different jobs lie behind the four situations above — which is why there is no honest single quote. The situation itself does most of the work of moving your cost. Where the vehicle is counts too, and whether our van can safely get to it, after the proportion of petrol to what that tank holds.
What got in, how much, and whether it has run — three queries our technicians ask before pricing, not after, for precisely that reason. A range turns into a straight figure once those answers are in.
About Tettenhall Wood itself
Tettenhall Wood is a suburban area located on the outskirts of Wolverhampton, near the River Staffordshire, with a mix of housing types but predominantly detached homes. Tettenhall Wood sits at an elevation of around 140 metres, close to the nearby places of Compton, Finchfield, and Tettenhall. Tettenhall Wood is situated approximately 2 miles from Wolverhampton city centre, making it a popular residential area. Tettenhall Wood has a population of around 4316 people, according to recent estimates.
Fuel drain cover in Tettenhall Wood and across West Midlands
Tettenhall Wood sits in the WV postcode area, and our teams that answer petrol in diesel call-outs there work the spots around it as well — Compton, Finchfield and Tettenhall among them. A forecourt, a supermarket car park, a lay-by or your own drive are all spots our engineers work, and your car does not need to move to us.
At the pump around Tettenhall Wood, still?
No position is better: that's where you are. Phone, and leave it turned off.