Should You Worry? Petrol in a Diesel Car in Black Lake
Provided it has not been started, you can worry far less than you probably are. Petrol sitting in a diesel tank does nothing to the engine until something draws it through your fuel system — the ignition priming your pump, your starter, or the drive itself. So the truthful answer to the first question anyone in Black Lake asks, "have I wrecked it?", is usually no. Keep it like that: leave the engine off then call Petrol in Diesel. What petrol actually does to a diesel, how to judge how far it has gone, and how to stop it from happening a second time: that's the rest of this page.
Petrol in a diesel: what does it do to the motor?
Two tasks fall to diesel on its route through a motor. It ignites, and before it combusts it lubricates. Very fine clearances are built into your injectors and your high-pressure pump, and just the diesel flowing through stops their surfaces grinding together.
Petrol does the first job badly and the second not at all. A pump running on a petrol blend is wearing itself out, since petrol is runnier than diesel and strips out the lubrication your fuel system depends on. Petrol is also made to resist igniting under compression — the opposite of what a diesel needs from its fuel — and that is where any rattling starts.
Together, those make the shape of the trouble clear. Not contact but circulation is what does the damage. Where the petrol is only inside the 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 moves on with your fuel to the injectors downstream.
Four scenarios our technicians see in Black Lake: how bad is petrol in a diesel?
Fuelled up, never started. The best case there is. That petrol is inside the tank and just your tank, and the job is a drain and a flush where the car sits. This is the one scenario that can only truly take place on a forecourt, because anywhere else your car has been driven to get there.
Started for a moment, or only the ignition on. Once primed, the fuel system has pulled petrol from that tank up to the filter and your lines. Drain, flush, see to the filter: still normally straightforward.
Those few miles on the road were your pump labouring on fuel thinned by petrol the whole way. Tank, lines, filter, then fresh fuel put through the entire circuit: that is the work, and the way your car was driven counts as much as the distance. On the school run to Hateley Heath Academy, the distance is short. Very different again: a run to Wolverhampton, under 10 miles away, or some distance on the M5, under 3 miles from Black Lake, where the motor kept labouring hard.
It protested, and only then stopped: smoke, rattling, a throttle gone soft, an idle gone uneven. The motor is telling you the fuel is no longer behaving like diesel. Whether it's the verge on Coles Lane, a lay-by or a side road, stop where you are and leave it. Lasting damage is very uncommon when a car is pulled over quickly, and the drain and flush that still come first deal with it.
Petrol in a diesel stories Black Lake drivers hear
Myth: "Fill it the rest of the way with diesel and it'll be fine." It will not. Topping up removes nothing; it gives you a fuller tank of the same mixture. That advice assumes a diesel fuel system handles petrol by percentage. It doesn't.
Not so: a current diesel copes with a bit of petrol. If anything, the opposite. More precise components and higher pressure are the way a current diesel runs its fuel, and that makes the protection matter more, not less.
Myth: "If it starts and drives, there's no damage done." This is the one that catches drivers. A petrol engine fed diesel usually will not run, so the motorist stops and the damage stops with them. A diesel fed petrol normally starts, idles and drives away as if nothing has happened, while your pump grinds. Being able to run isn't proof of being fine.
An old fix for a separate issue lies behind this one. Myth: "Add some two-stroke oil and drive the car home." None of what petrol diluted is put back by it — and afterwards, the tank still contains the petrol.
Myth: "Drain that tank yourself and you're sorted." After the engine has been run, some of that petrol is no longer in the tank: it's in the filter and the lines, and it goes straight back through the pump on your next start. It's also really risky to drain petrol into a can at the roadside.
How petrol ends up: petrol in a diesel
Nobody does it on purpose, and it is rarely carelessness. The forecourt makes it easy: the petrol nozzle is the slimmer of the two, and it slides into a diesel filler with almost no resistance, whilst a diesel nozzle mostly will not go into a petrol car at all. So the mistake runs one way.
The moment habit stops matching the car is the moment it takes place. A new vehicle, a hire car or a courtesy car. One petrol and one diesel on the drive of the same household. A forecourt you know, only with its pumps laid out differently. A hurried fill en route to Dudley Port with a train to catch. Precisely the moment it happens: after years of driving petrol, someone fills a diesel BMW 3 Series for the first time. With rain, a call arriving, or a car full of children to deal with, the hand simply does what it has always done.
Avoiding petrol in a diesel next time you fill up in Black Lake
- Not every forecourt in the UK follows green for unleaded and black for diesel, even if most usually do. Read the pump's label; the colour is just a hint.
- In a motor you do not know, look inside the flap over the filler or at the cap before the first fill: many vehicles state the fuel there.
- A coloured fob or a sticker on the diesel's key achieves more than any amount of meaning to remember, for a home with one of each.
- It seems silly and it works: on your first fill in a new or hired car, say "diesel" aloud before you take the nozzle off the petrol pump.
- Thinking about something else is when this becomes an easy mistake to make, and so tuck the phone away then keep your mind on the pump.
- Some diesels come with a filler designed to block a petrol nozzle, and devices you can add exist for vehicles without one. Such an inhibitor helps up to a point — as a safety net, not a reason to stop checking the petrol pump.
- As soon as you notice, stop: less petrol in the tank means a weaker mixture. What to do next doesn't change, though — still don't fire it up.
Already put petrol in a diesel around Black Lake?
Then the order of things is brief. Don't fire it up, and don't turn your ignition on. Yet on the forecourt, at BP or anywhere else? Ask the staff to help you push it away from the petrol pump. Next, 0333 366 0103. We'll ask what got in, about how much, and if it's been run.
AdBlue, not petrol? Then tell us. Corrosion and deposits, not lost protection, make it a separate issue — Black Lake has a page just for it.
Black Lake petrol in a diesel jobs: why one costs more than another
There is no honest single price for this, since the four scenarios above are four separate tasks. The scenario itself does most of the work of moving the cost. Where the vehicle is counts too, and whether a van can safely reach it, after the share of petrol to what your tank takes.
What got in, how much, and if it's run — three queries our technicians ask before pricing, not after, for exactly that reason. Those replies turn a range into a straight figure.
About Black Lake and where it is
Black Lake is a suburban area in the West Midlands, situated on the riverside with nearby neighbourhoods including Hill Top and Harvills Hawthorn. Black Lake sits at an elevation of 161 metres, approximately 6 miles from Wolverhampton and 107 miles from London. Black Lake has a population of around 7716 people, predominantly living in semi-detached housing. Black Lake is part of the larger West Midlands conurbation, with its residents benefiting from proximity to local amenities and transport links.
Fuel drain cover around Black Lake and across West Midlands
Petrol in diesel jobs around Black Lake — part of the B postcode area — go to teams that also cover the spots around it, Hill Top, Harvills Hawthorn and Hateley Heath included. The vehicle doesn't need to come to us: our technicians drain on a forecourt, in a supermarket car park, in a lay-by or on your own drive.
Black Lake: still at the petrol pump?
Then you're in the best place there can be. Ring, and leave it turned off.