How Worried Should You Be? Petrol in a Diesel Car in Thundersley
Probably less than you are now — as long as no one has started it. "Have I wrecked it?" is the first question everyone around Thundersley asks, and the honest answer is normally no, since petrol resting in a diesel tank hurts nothing till it's dragged through the system — by ignition priming, by your starter, or by driving. Petrol in Diesel is who to phone, with your engine kept off, and so it remains that way. The rest of this page explains what petrol really does to a diesel, how to tell how far it has got, and how to make sure it does not happen to you a second time.
Petrol in a diesel: what does it do to your engine?
Two jobs fall to diesel on its journey round a motor. It combusts, and before it burns it lubricates. Very fine gaps are built into the injectors and your high-pressure pump, and just the diesel flowing through stops those surfaces grinding together.
Petrol handles the first job poorly and the second not at all. Being less viscous than diesel, petrol strips away the lubrication a fuel system needs, so a pump on that mixture to wear itself. It is equally made to resist igniting under compression — the reverse of what a diesel needs — which is why you hear the knocking.
The shape of the issue is clear once you put those together. Contact does not do the harm — movement does. Any tank with petrol in it is a fuel fault. The beginning of a mechanical problem is a pump that has been running on that petrol — and whatever a worn pump sheds moves on with your fuel to the injectors beyond it.
How bad is petrol in a diesel? Four scenarios our technicians see in Thundersley
Filled but never started — the best it gets. On a forecourt, and truly only there, that petrol is still confined to your tank — since anywhere else the vehicle was driven to get to it. The job is emptying and flushing on the spot.
The ignition turned on, or a brief start. The fuel system has been bled, so petrol has left the tank and reached your filter and your lines. Normally nothing more than clearing, rinsing and seeing to the fuel filter, and so still straightforward.
The pump has spent a couple of miles on diluted fuel — that's what driving the vehicle meant. Tank, lines, filter, then fresh fuel run through the whole circuit: that's the work, and the way the vehicle was driven matters as much as the miles. On the school run to Kingston Primary School, the miles is short. Very different again: a run to Southend-on-Sea, under 10 miles away, or some distance on the M25, under 15 miles from Thundersley, where your engine never stopped running hard.
Clattering, a lumpy idle, smoke, a throttle gone soft: driven until it complained. The fuel isn't behaving like diesel any more, and the engine is telling you. Stop wherever you are — the verge on Church Road, a lay-by, a side street — and leave the vehicle there. Permanent damage is very uncommon if a vehicle is pulled over soon, and the fuel drain and flush that still go first sort it out.
Petrol in a diesel stories Thundersley drivers hear
"Top it up the rest of the way with diesel and it will be fine" — a myth. It won't. Nothing comes out when you top up — your tank simply holds more of the same blend. The idea behind that guidance — that diesel fuel systems accept petrol by percentage — is wrong.
Myth: "A current diesel can cope with a bit of petrol." If anything, the reverse. A newer diesel sends its fuel through more precise parts at higher pressure, which 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. Diesel in a petrol motor normally means a motor that will not run: the motorist stops, and so does the damage. Feed petrol to a diesel and it generally starts, idles and drives away as if nothing has happened — all while its pump is wearing. Running doesn't mean fine.
Myth: "Add some two-stroke oil and drive it home." It is an outdated workaround for a separate issue. None of what petrol thinned is put back by it — and afterwards, that tank still holds that petrol.
"Drain it yourself and you're sorted" — a myth, because after it's been running some petrol sits in the fuel filter and lines, ready to go straight back through the pump at the next start. And, a can of petrol filled at the roadside is truly dangerous.
How does petrol in a diesel occur?
It is seldom carelessness, and no one does it on purpose. The forecourt makes it easy: the petrol nozzle is the narrower of the two, and it slides into a diesel filler with almost no resistance, while a diesel nozzle generally will not go into a petrol vehicle at all. So the mistake runs one way.
The moment routine stops matching the vehicle is the moment it occurs. Courtesy car, hire car, or a vehicle that is brand new. One petrol and one diesel on the drive of the same household. The pumps in a different order on a familiar forecourt. A train to catch, and a rushed fill on the way to Benfleet. The first fill-up in a diesel Ford Focus after years of driving petrol is precisely the moment it happens. The hand repeats what it has always done when you add rain, a phone call or a back seat full of children.
How to prevent petrol in a diesel at your next fill-up in Thundersley
- The label is what matters, and so check the pump rather than the colour: in the UK unleaded handles are usually green and diesel black, yet not on each forecourt.
- The first fill in a new car is the time to check the filler flap — inside it, or on the cap, plenty of vehicles state which fuel they take.
- A coloured fob or a sticker on your diesel's key does more than any amount of meaning to remember, in a house with one of each.
- It sounds silly and it works: on your first fill in a new or hired car, say "diesel" aloud before you lift the nozzle off the petrol pump.
- Whilst you are thinking about something else, this is an easy mistake to make — so put your phone away.
- Up to a point, a misfuel inhibitor helps: some diesels come with a filler built to refuse a petrol nozzle, and add-on devices exist for the remainder. Treat it as a backstop, and keep reading the pump.
- Spotting it halfway? Stop there and then. A thinner mixture follows from less petrol inside the tank, but your next step remains the same: don't start the car.
Thundersley: already put petrol in a diesel?
Short and simple, then, is the order of things. Don't start the car, and do not turn the ignition on. If you are still at the forecourt — Esso or anywhere else — ask the staff to help you push the car away from the petrol pump. What got in, about how much, and if it has run: tell us that when you phone 0333 366 0103.
AdBlue, not petrol? Then tell us. Corrosion and deposits, not lost protection, make it a separate problem — Thundersley has a page all for it.
One petrol in a diesel task in Thundersley costs more than another. Why?
The four situations above are four different tasks, so no single price for this would be honest. What shifts the cost is mostly which of them you're in. Two things follow that: the petrol that got in as a proportion of what your tank takes, then the spot the car is in and whether a van can get to it safely.
That's why our engineers ask three queries before costing instead of after: what went in, how much, and if it has run. Those replies turn a range into a straight figure.
About Thundersley, briefly
Thundersley is a locality in Essex, situated approximately 30 miles east of London and 6 miles northwest of Southend-on-Sea. Thundersley sits in a relatively low-lying area at an elevation of around 78 metres, surrounded by other nearby places such as New Thundersley, Tarpots, and South Benfleet. Thundersley has a population of around 2169 people, predominantly living in semi-detached housing.
Across Essex and around Thundersley: fuel drain cover
Petrol in diesel calls around Thundersley — part of the SS postcode area — go to teams that also cover the spots about it, New Thundersley, Tarpots and South Benfleet included. A forecourt, a supermarket car park, a lay-by or your own drive are all places we work, and your vehicle doesn't need to come to us.
Thundersley: still at the petrol pump?
In that case, you couldn't be in a better position. Keep it turned off, and ring.