Petrol in a Diesel Car in Dry Hill: How Worried Should You Be?
Likely less than you are now — as long as nobody has started the vehicle. Until the ignition primes your pump, your starter cranks, or the vehicle is driven, petrol in a diesel tank just rests there and does no harm. Which means the truthful reply to that first Dry Hill query — "have I ruined it?" — usually no. Petrol in Diesel is who to call, with your engine left off, so it remains that way. The rest of this page explains what petrol really does to a diesel, how to judge how far it has got, and how to make sure it does not happen to you again.
Petrol in a diesel: what does it do to the motor?
Passing through a motor, diesel does two things at once. It burns, and before it burns it protects. Very fine gaps are built into the fuel injectors and the high-pressure fuel pump, and only your diesel running through stops their surfaces grinding together.
Poorly at the first, not at all at the second: that's petrol. It's runnier than diesel and takes away the lubrication your fuel system rests on, and so a pump running on a petrol blend is a pump wearing itself. And petrol is designed to resist igniting under compression, which is the opposite of what a diesel needs from its fuel. That is where the knocking comes from.
The shape of the problem is plain when you put those together. Contact does not do the harm — movement does. A tank with petrol in it is a fuel fault. Once the pump has been working on that petrol, a mechanical problem has started: anything shed by a pump that's grinding travels onward to your injectors with the fuel.
Four situations we see around Dry Hill: how serious is petrol in a diesel?
Fuelled, and not started: no case is better. At a forecourt, and truly only there, the petrol is still confined to your tank — because anywhere else the car was driven to get to it. The job is draining and purging on the spot.
Started for a second, or just the ignition on. With your system primed, the fuel lines and filter already contain petrol that has come from your tank. Usually nothing more than clearing, purging and seeing to your filter, and so still easy.
Driven a couple of miles. Now the pump has spent those miles working on diluted fuel. Mileage is only half of that; how hard it was driven counts just as much. Either way this work includes the tank, your lines, the fuel filter and clean fuel through the whole system. Short trips, like the school run to Portishead Primary School, are one thing. A run as far as Bristol, under 10 miles away, is a very different task. So is any distance on the M5, under 3 miles from Dry Hill, where the motor has been running hard throughout.
It protested, and only then stopped: smoke, knocking, a throttle gone soft, an idle gone ragged. The motor is telling you the fuel is no longer behaving like diesel. Whether it's the verge on Combe Avenue, a lay-by or a side road, stop there then leave it. A car stopped quickly very seldom has permanent damage, as the drain and the flush, which still come first, sort it out.
What Dry Hill motorists get told about petrol in a diesel — and the stories in it
It will not be fine. The myth: "Fill it the rest of the way with diesel and it'll be." Nothing is removed when you top up — the tank simply holds more of the same blend. That advice supposes a diesel fuel system tolerates petrol by percentage. It doesn't.
Myth: "A modern diesel can cope with a bit of petrol." If anything, the reverse. More precise components and higher pressure are how a current diesel runs its fuel, and that makes the protection matter more, not less.
The myth that catches motorists out: if it starts and drives, it must be unharmed. The motorist of a petrol motor fed diesel normally has no choice but to stop, because it will not run, and the damage stops with them. Nothing looks to have happened when a diesel fed petrol fires up, ticks over and drives away, which it usually does; meanwhile your pump wears. A running engine doesn't mean fine.
Myth: a two-stroke additive lets you to drive home. It is an old workaround, supposed for another problem. None of what petrol diluted gets put back by it — and afterwards, the tank still holds the petrol.
Myth: "Drain the tank yourself and you are sorted." After your engine has run, some of the petrol is no longer inside your tank: it is in the filter and the lines, and it goes right back through your pump on your next start. Besides, petrol emptied into a can by the road is genuinely hazardous.
How does petrol in a diesel take place?
On purpose? Never. Through carelessness? Rarely, if ever. 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, while a diesel nozzle mostly won't go into a petrol car at all. So the error runs one way.
It happens when routine and the car stop matching. A new vehicle, a hire car or a courtesy car. Households running one of each, petrol and diesel. Your usual forecourt, its pumps now in a different order. Fuelling up in a rush en route to Avonmouth, with a train to catch. Exactly the moment it takes place: after years of driving petrol, someone fills a diesel Renault Clio for the first time. Add rain, a phone call or a back seat full of children, and the hand does what it has always done.
Dry Hill drivers: how to prevent petrol in a diesel next time
- Check the pump, not the colour. In the UK unleaded handles are usually green and diesel black, but not on each forecourt. The label is what matters.
- Check your filler flap. Many vehicles state the fuel type inside the flap or on the cap. Look at it on your first fill in any car you don't know.
- Mark 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 comes off the pump the first time you fill a hired or new motor, say "diesel" out loud. Daft, yes, yet it does the trick.
- Tuck the phone away. This is an easy mistake to make while you are thinking about something else.
- A misfuel inhibitor helps, up to a point. Some diesels have a filler designed to block a petrol nozzle, and add-on devices exist for motors without one. They are a backstop, not a reason to stop reading the petrol pump.
- Noticing it halfway? Stop at once. A weaker mixture follows from less petrol in your tank, yet the next stage stays the same: do not fire it up.
Already put petrol in a diesel around Dry Hill?
In that case, there's only a short order of things. Don't turn the ignition on, and do not fire it up. If you're still at the forecourt — Shell or anywhere else — ask the attendants to help you push the vehicle clear of the petrol pump. What was put in, about how much, and if it has run: tell us those when you call 0333 366 0103.
Corrosion and deposits are the problem with AdBlue, where petrol means lost protection. So if it was AdBlue, say so — and see its own Dry Hill page.
One petrol in a diesel job in Dry Hill costs more than another. Why?
The four situations above are four different tasks, so no single quote for this would be honest. The situation itself does most of the work of moving your cost. Two things follow that: the petrol that went in as a share of what that tank holds, then the place your car is in and whether a technician can get to it safely.
That's why our technicians ask three questions before quoting instead of after: what got in, how much, and if it's run. Given the replies, there is a straight figure instead of a range.
About Dry Hill and where it is
Dry Hill is a suburban area located near the coast in Somerset, with an elevation of 55 metres and situated approximately 7.8 miles from Bristol. Dry Hill sits near several other residential areas, including Portishead, West Hill, and Woodhill, and is characterized by its semi-detached housing. Dry Hill is also relatively close to major cities, with London being around 113.9 miles away. Dry Hill has a population of around 4257 people.
Across Somerset and around Dry Hill: fuel drain cover
Dry Hill waits in the BS postcode area, and the teams that answer petrol in diesel calls there work the locations around it as well — Portishead, West Hill and Woodhill among them. The car does not need to come to us: our technicians drain at a forecourt, in a supermarket car park, in a lay-by or on your own driveway.
At the pump around Dry Hill, still?
Then, you couldn't be in a better position. Keep it off. Ring.