Should You Worry? Petrol in a Diesel Car in Coedpoeth
Less than you likely are, provided it has not been started. Petrol resting in a diesel tank does nothing to your engine till something pulls it through the fuel system — your ignition priming your pump, your starter, or the drive itself. So the fair answer to the first query everyone around Coedpoeth asks, "have I wrecked it?", is generally no. Leave your motor off and phone Petrol in Diesel — that keeps it like that. Keep reading for three things: the effect petrol has inside a diesel motor, the signs of how far it has spread, and the way to make sure you never repeat it.
Petrol in a diesel: what does it do to your engine?
On its way through an engine, diesel has two jobs. It lubricates first, and after that does it burn. Your high-pressure pump and the injectors are designed to very fine clearances, and your diesel passing through them is what keeps those surfaces from wearing against each other.
Badly at the first, not at all at the second: that's petrol. The clattering comes from petrol being designed not to ignite when compressed, which is precisely the opposite of what a diesel needs. On top of that it is runnier than diesel, it strips out the lubrication your system hinges on, and any pump working on that mixture is wearing itself.
Taken together, they make clear what shape the issue takes. The damage is done by movement, not by contact. Where the petrol is only inside the tank, it is an issue of fuel, nothing more. The start of a mechanical problem is a pump that has been running on that petrol — and whatever a worn pump sheds travels on with your fuel to the fuel injectors beyond it.
Four scenarios our engineers see in Coedpoeth: how bad is petrol in a diesel?
Fuelled but not once started — the best it gets. On a forecourt, and truly only there, that petrol is still confined to that tank — since anywhere else the vehicle was driven to get to it. The task is draining and purging on the spot.
Ignition on, or started for a second. Once primed, the fuel system has drawn petrol from your tank up to your filter and your lines. That is generally still an easy task — a drain, a flush, and your filter dealt with.
Driven a few miles. Now your pump has spent those miles labouring on thinned fuel. How hard your car was driven matters as much as how far, and the work takes in the tank, the fuel lines, your filter and clean fuel through the entire system. Driving the children to the local primary school is one kind of trip. Very different again: a run to Wrexham, under 5 miles away, or some miles on the M53, under 15 miles from Coedpoeth, where your engine never stopped working hard.
Clattering, an uneven idle, smoke, a throttle gone soft: driven till it complained. The fuel is not acting like diesel any more, and the motor is saying so. Whether it is the verge on Heol Maelor, a lay-by or a side road, stop there then leave it. A car stopped soon very rarely has lasting damage, since the fuel drain and the flush, which still come first, sort it out.
What Coedpoeth motorists get told about petrol in a diesel — and the myths in it
"Top it up the rest of the way with diesel and it'll be fine" — a myth. It won't. Nothing is removed by topping up — you're left with a bigger tank, still the same mix. The assumption behind the guidance — that diesel fuel systems tolerate petrol by percentage — is wrong.
Myth: "A newer diesel can cope with a bit of petrol." If anything, the opposite. Smaller parts and higher pressure are how 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 fools drivers. The motorist of a petrol motor fed diesel normally has no choice but to stop, since it will not run, and the harm stops there. Nothing seems to have happened when a diesel fed petrol fires up, ticks over and drives away, as it usually will; meanwhile your pump wears. Running doesn't mean fine.
An old workaround for a separate issue is behind this one. Myth: "Add some two-stroke oil and drive it home." The petrol is still in the tank after that, and what it has weakened is not put back.
Myth: "Drain the tank yourself and you are sorted." After the engine has been run, some of the petrol is no longer inside the tank: it is in your filter and the lines, and it goes straight back through the pump at the next start. Also, a can of petrol drained at the kerbside is truly risky.
Why petrol in a diesel takes place at all
No one does it on purpose, and it's seldom carelessness. The forecourt makes it simple: the petrol nozzle is the smaller of the two, and it slips into a diesel filler with almost no resistance, whilst a diesel nozzle generally will not go into a petrol motor at all. So the slip runs one way.
Habit and the vehicle getting out of step is how it happens. Courtesy car, hire car, or a car that's brand new. Households running one of each, petrol and diesel. A well-known forecourt with the pumps in a different order. A hurried fill en route to Gwersyllt with a train to catch. A new-to-you diesel Volkswagen Golf, its first fuelling, and a motorist accustomed to petrol: precisely when it happens. The hand does what it has always done once 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 around Coedpoeth
- Not every forecourt in the UK follows green for unleaded and black for diesel, though most generally do. Read the petrol pump's label; the colour is only a hint.
- In a vehicle you don't know, look inside the flap over your filler or at the cap before the first fill: many cars state the fuel there.
- Label 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 meaning to remember.
- Before the nozzle leaves the petrol pump the first time you fuel a hired or new motor, say "diesel" aloud. Daft, yes, but it works.
- Mistakes like this are easy to make whilst your mind is on something else, and so the phone goes away.
- Some diesels have a filler built to reject a petrol nozzle, and devices you can add are available for motors without one. Such an inhibitor helps up to a point — as a safety net, not a reason to stop checking the petrol pump.
- Noticing it mid-fill? Stop at once. A thinner blend results from less petrol inside the tank, yet your next stage stays the same: don't fire it up.
Coedpoeth: already put petrol in a diesel?
Short and simple, then, is the order of things. Leave it unstarted, with your ignition off as well. If you are still on the forecourt — Asda or anywhere else — ask the staff to help you push it away from the pump. Then call 0333 366 0103 and tell us what went in, about how much, and if it's run.
Say so if it was AdBlue instead of petrol: it's a separate issue, with its own page for Coedpoeth, because AdBlue brings corrosion and deposits rather than lost protection.
Why one petrol in a diesel task around Coedpoeth costs more than another
There's no honest single price for this, because the four situations above are four separate tasks. Mostly, your cost moves with which situation you're in. Where the car is matters too, and whether a technician can safely reach it, after the ratio of petrol to what that tank takes.
That is why our engineers ask three questions before costing instead of after: what went in, how much, and whether it's run. Those answers change a range into a straight figure.
About Coedpoeth and where it is
Coedpoeth is a village situated on the banks of a river in northeast Wales, approximately 3 miles from Wrexham. Coedpoeth sits at an elevation of 241 metres, overlooking the surrounding countryside. Coedpoeth has a mix of housing types, but semi-detached homes are the most common. Coedpoeth is located near other small villages, including Talwrn and Bryngwyn.
Fuel drain cover across Wrexham, Coedpoeth included
Talwrn, Bryngwyn and The Smelt are among the locations near Coedpoeth that the same teams work, answering petrol in diesel jobs across Coedpoeth's LL postcode area. The vehicle doesn't need to move to us: we drain at a forecourt, in a supermarket car park, in a lay-by or on your own drive.
Coedpoeth: still at the petrol pump?
The best place there is, then — that is where you are. Keep it off. Phone.