Bromsgrove: Petrol in a Diesel Car? How Worried to Be
Likely less than you are now — provided no one has started it. Till the ignition primes your pump, the starter turns, or your vehicle is driven, petrol in a diesel tank just sits there and does nothing. Which means the truthful reply to that first Bromsgrove question — "have I wrecked it?" — usually no. Petrol in Diesel is who to call, with your motor left off, so it remains that way. Keep reading for three things: the effect petrol has inside a diesel motor, the signs of how far it has got, and the way to make sure you don't do it again.
Inside the motor: what petrol in a diesel does
Passing through a motor, diesel is doing two jobs at the same time. Before it ignites, it protects — then it ignites. Your high-pressure pump and your injectors are designed to extremely fine clearances, and your diesel passing through them is what keeps those surfaces from wearing down against each other.
The second job petrol doesn't do at all, and the first it does poorly. It's runnier than diesel and strips away the protection your 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's where the clattering comes from.
Combined, those make the shape of the issue clear. It is circulation that causes the damage, not contact. Petrol in a tank is a fuel fault. The start of a mechanical one is a pump that has been labouring on that petrol — and whatever a worn pump sheds moves on with your fuel to your injectors beyond it.
How bad is petrol in a diesel? Four situations our engineers see around Bromsgrove
Filled but never started — as good as it gets. At a forecourt, and genuinely only there, that petrol is still limited to that tank — since anywhere else your car was driven to get to it. The task is draining and flushing on the spot.
A brief spell of running, or just the ignition on. With your system primed, the lines and filter already hold petrol that came from the tank. Drain, flush, see to the filter: still normally straightforward.
Driven a couple of miles. Now your pump has spent these miles working on thinned fuel. How hard the vehicle was driven counts as much as how far, and the work takes in the tank, your lines, the filter and clean fuel through the whole system. Short trips, such as the school run to Meadows First School, are one thing. Very different a second time: a trip to Birmingham, under 15 miles away, or any miles on the M5, under 3 miles from Bromsgrove, where the motor kept labouring hard.
Driven till it complained. Knocking, a lumpy 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 Windsor Street, a lay-by, a side street — and leave the vehicle where it is. The drain and flush still come first, and they deal with it: when a car is pulled over quickly, permanent damage is very uncommon.
Myths Bromsgrove 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 will be." Nothing is removed by topping up — you are left with a fuller tank, still the same mixture. The idea behind the guidance — that diesel fuel systems tolerate petrol by percentage — is wrong.
"Modern diesels can handle a little petrol" — a myth, and closer to the opposite. More precise components and higher pressure are the way a current diesel runs its fuel, and that makes the lubrication count more, not less.
This is the one that fools drivers. Myth: "If it starts and drives, there's no damage done." Any petrol motor fed diesel usually will not run, so the driver stops and the damage stops with them. Whilst the pump wears, a diesel fed petrol normally starts, ticks over and drives away as if nothing has happened. Running isn't the same as fine.
Myth: "Add some two-stroke oil and drive the vehicle home." It's an old fix for a different issue. None of what petrol thinned is put back by it — and afterwards, your tank still contains the petrol.
The next start draws petrol back round the pump out of the fuel lines and the fuel filter, where some of that sits after the engine has been run. That's why draining your tank yourself doesn't sort it — a myth. Clearing petrol into a can by the roadside is also truly hazardous.
How petrol ends up: petrol in a diesel
It's seldom carelessness, and nobody does it on purpose. The forecourt makes it simple: the petrol nozzle is the slimmer of the two, and it slips into a diesel filler with almost no resistance, while a diesel nozzle mostly will not go into a petrol vehicle at all. So the slip runs one way.
Habit and the vehicle falling out of step is when it takes place. Hire cars, courtesy cars, and motors that are new to you. Two cars on one driveway, one petrol, one diesel. A well-known forecourt with the pumps in a different order. A train to catch, and a rushed fill on the way to the nearest station. A new-to-you diesel Renault Clio, its first fuelling, and a motorist accustomed to petrol: precisely when it occurs. Your hand repeats what it has always done once you add rain, a phone call or a back seat full of kids.
Bromsgrove motorists: how to prevent petrol in a diesel next time
- Check the petrol pump, not the colour. In the UK unleaded handles are normally green and diesel black, yet not on each forecourt. The label is what matters.
- In a vehicle you don't know, look inside the flap over the filler or at the cap before your first fill: plenty of vehicles print the fuel there.
- Label the key. In a house with one of each, a coloured fob or a sticker on the diesel's key does more than any amount of meaning to remember.
- It sounds daft and it works: on the first fill in a new or hired car, say "diesel" out loud before you take the nozzle off the petrol pump.
- While you're thinking about something else, this is an easy mistake to make — so put your phone away.
- Some diesels come with a filler designed to refuse a petrol nozzle, and devices you can add are available for cars without one. Such an inhibitor helps up to a point — as a safety net, not a reason to stop reading the petrol pump.
- Spotting it halfway? Stop at once. A weaker mix follows from less petrol in your tank, but the next step remains the same: do not start the vehicle.
Already put petrol in a diesel in Bromsgrove?
Then, there is just a short order of things. Do not start it, and don't turn your ignition on. Ask the attendants to help you roll it away from the petrol pump if you are still on the forecourt, whether that is BP or anywhere else. What went in, about how much, and if it has run: tell us that when you phone 0333 366 0103.
If it was AdBlue and not petrol, say so. That's a separate fault — corrosion and deposits instead of lost lubrication — and it has its own page for Bromsgrove.
Why one petrol in a diesel job around Bromsgrove costs more than another
There's no fair single quote for this, since the four scenarios above are four separate jobs. What moves the cost is mostly which of them you're in. Next it's the proportion — how much petrol got in against how much the tank holds — and after that where the car is and whether our van can reach it safely.
What got in, how much, and whether it has run — three queries our engineers ask before costing, not after, for precisely that reason. A range becomes a straight figure once those replies are in.
About Bromsgrove
Bromsgrove is a town in north-east Worcestershire, situated on the River Bromsgrove, with a mix of semi-detached housing and other residential areas. Bromsgrove sits at an elevation of around 93 metres, near the Lickey Hills and close to the M5 and M42 motorways. Bromsgrove is located near several smaller communities, including Stoney Hill, Sidemoor, and Red Cross, and is within commuting distance of Birmingham. Bromsgrove has a population of approximately 23,488 people, with easy access to the wider West Midlands region.
Fuel drain cover in Bromsgrove and across Worcestershire
Stoney Hill, Sidemoor and Red Cross are among the locations around Bromsgrove that the same teams work, answering petrol in diesel call-outs across Bromsgrove's B postcode area. We drain where the vehicle 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 in Bromsgrove?
No position is better: that is where you now are. Switched off it stays; then phone.