Catteshall: Petrol in a Diesel Car? How Worried to Be
Unstarted? Then less worried than you probably feel. "Have I wrecked it?" is the first question everyone around Catteshall asks, and the honest answer is generally no, because petrol left in a diesel tank harms nothing till it's dragged through your fuel system — by ignition priming, by the starter, or by being driven. Petrol in Diesel is who to phone, with your engine left off, and so it stays that way. Read on for three things: the effect petrol has inside a diesel motor, the clues of how far it has got, and ways to make sure you never do it again.
Your engine and petrol in a diesel: what goes on
Passing through a motor, diesel does two things at the same time. It protects first, and only then does it burn. The high-pressure fuel pump and your injectors are built to very fine clearances, and the diesel passing through them is what keeps those surfaces from grinding against each other.
Of those two tasks, petrol manages the first badly and the second not at all. A pump working on a petrol blend is wearing itself out, because petrol is thinner than diesel and strips out the lubrication the fuel system depends on. Petrol is also designed to resist igniting under compression — the opposite of what a diesel needs from its fuel — and that's where the rattling starts.
Combined, those make the shape of the problem clear. Contact does not do the harm — circulation does. Petrol in a tank is a fuel problem. Once your pump has been running on that petrol, a mechanical issue has begun: anything shed by a pump that's grinding travels downstream to your injectors with the fuel.
Catteshall, petrol in a diesel: four situations, from mild to serious
Filled up, not once started. The best case there is. On a forecourt, and really only there, that petrol is still limited to your tank — because everywhere else the vehicle was driven to get to it. The task is emptying and rinsing on the spot.
The ignition turned on, or a short start. Petrol has come out of your tank and reached the fuel filter and the fuel lines, because the system has been primed. Normally nothing more than clearing, flushing and seeing to your filter, and so still simple.
Your pump now worked a few miles on weakened fuel — that's what driving it does. How hard your car was driven counts as much as how far, and the work covers your tank, the fuel lines, the filter and clean fuel through the whole system. Short trips, like the school run to Godalming Junior School, are one matter. Driving as far as Chichester, under 50 miles away, makes a very different task — as does any distance on the M25, under 15 miles from Catteshall, with the motor working hard all the way.
Driven until it complained. Rattling, a lumpy idle, smoke, a throttle that has gone soft. That's the motor telling you its fuel no longer is acting like diesel. Pull up wherever you are — the verge on Grange Close, a lay-by, a side street — and leave the vehicle there. Lasting damage is very rare if a car is pulled over soon, and the drain and flush-through that still come first take care of it.
What Catteshall motorists get told about petrol in a diesel — and the stories in it
Myth: "Fill it the rest of the way with diesel and it will be fine." It will not. Nothing is removed by topping up — you're left with a bigger tank, still the same mixture. The assumption behind the guidance — that diesel fuel systems tolerate petrol by percentage — is wrong.
"Current diesels can handle a little petrol" — a myth, and nearer the reverse. A current diesel sends its fuel through smaller parts at higher pressure, which 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." Feed diesel to a petrol motor and it normally won't run, so the motorist stops — and the harm stops with them. A diesel fed petrol usually starts, ticks over and drives away as though nothing has happened, whilst your pump wears. A running engine does not mean fine.
Myth: a two-stroke additive makes it safe to drive home. It was an old workaround, supposed for another fault. It doesn't put back what petrol has thinned, and that petrol is still in the tank after that.
The next start sends petrol back round your pump out of the fuel lines and your filter, where some of it ends up once the engine has been run. That's why draining your tank yourself doesn't leave you sorted — a myth. And, a can of petrol filled at the kerbside is genuinely hazardous.
Why petrol in a diesel occurs at all
It's seldom carelessness, and no one does it on purpose. A diesel nozzle generally will not fit a petrol car, yet the slimmer petrol nozzle goes into the filler of a diesel nearly without resistance — so forecourts make this one mistake simple, and just in one direction.
The moment habit stops matching the car is the moment it happens. Courtesy car, hire car, or a car that is new. A household with one petrol and one diesel on the drive. The pumps in a different order on a well-known forecourt. Rushing for a train at Farncombe and filling up en route. A new-to-you diesel Volkswagen Golf, its first fuelling, and a motorist accustomed to petrol: precisely when it occurs. With rain, a call coming in, or a car full of children to deal with, the hand simply does what it has always done.
Preventing petrol in a diesel next time you fill up around Catteshall
- Green for unleaded and black for diesel is normal in the UK — yet not on each forecourt. Go by the label on the pump, not the colour.
- Plenty of cars state the fuel type inside the filler flap or on the cap, and so check it on the first fill in a vehicle you don't know.
- A coloured fob or a sticker on your diesel's key does more than any amount of intending to remember, for a house with one of each.
- Say it before you lift it. On your first fill in a new or hired car, say "diesel" aloud before you take the nozzle off the pump. It seems daft and it works.
- Tuck the phone away. This is an easy mistake to make whilst you're thinking about something else.
- Up to a point, a misfuel inhibitor helps: some diesels come with a filler designed to block a petrol nozzle, and aftermarket devices are available for the remainder. Count it as a backstop, and keep checking the pump.
- As soon as you notice, stop: less petrol in that tank means a thinner mix. What to do next does not change, though — still don't start it.
Catteshall: already put petrol in a diesel?
Then, there's only a short order of things. Don't turn your ignition on, and do not fire it up. Yet at the forecourt, at Texaco or anywhere else? Ask the attendants to help you roll the car away from the petrol pump. What went in, about how much, and if it has run: tell us those when you phone 0333 366 0103.
If it was AdBlue instead of petrol, say so. That is a separate problem — corrosion and deposits instead of lost lubrication — and it has its own page for Catteshall.
One petrol in a diesel task around Catteshall costs more than another. Why?
An honest single price doesn't exist here: four scenarios, four separate tasks. What moves the cost is mostly which of them you are in. Two things come after that: the petrol that was put in as a proportion of what that tank holds, then the place the vehicle is in and whether a van can reach it safely.
Ahead of any quote, not after, we ask three queries: the fuel that went in, its volume, and if it's run. That is why. Those replies are what change a range into one firm number.
About Catteshall
Catteshall is a suburban area in Surrey, situated on the riverside with an elevation of 37 metres. Catteshall lies near the villages of Farncombe, Crownpits, and Busbridge, and is approximately 29.9 miles from London. Catteshall has a population of around 2090 people and predominantly consists of semi-detached housing. Catteshall is also relatively close to the city of Chichester, which is 25.6 miles away.
Catteshall and Surrey: where our fuel drain cover runs
Catteshall waits in the GU postcode area, and the teams that answer petrol in diesel calls there work the places near it as well — Farncombe, Crownpits and Busbridge among them. The vehicle doesn't need to move to us: our technicians drain on a forecourt, in a supermarket car park, in a lay-by or on your own drive.
Catteshall: still at the pump?
In that case, you couldn't be in a better place. Keep it off. Phone.