Petrol in a Diesel Car in Maple Cross: How Worried Should You Be?
Provided it has not been started, worry far less than you probably are. Until your ignition primes the pump, the starter cranks, or your vehicle is driven, petrol in a diesel tank just sits there and does no harm. Which means the truthful reply to that first Maple Cross query — "have I wrecked it?" — normally no. To keep the car like that, phone Petrol in Diesel then leave the motor switched off. Keep reading for three things: the effect petrol has inside a diesel engine, the signs of how far it has got, and the way to make sure you don't do it again.
Petrol in a diesel: what does it do to the motor?
Diesel does two jobs on its way through a motor. Before it burns, it lubricates — then it burns. The high-pressure pump and the injectors are designed to very fine gaps, and the diesel passing through them is what stops those surfaces from wearing against one another.
The second task petrol does not do at all, and the first it does badly. It is thinner than diesel and removes the lubrication the system depends on, and so a pump running on a petrol mix is a pump wearing itself. And petrol is made to resist igniting under compression, which is the reverse of what a diesel needs from its fuel. That is where the clattering comes from.
The shape of the trouble is plain once you put those together. It is circulation that does the damage, not contact. All a tank with petrol in it amounts to is a fuel issue. A pump that has been labouring on that petrol is the start of a mechanical one, and whatever a worn pump sheds travels on with your fuel to your injectors downstream.
Petrol in a diesel around Maple Cross: how serious is it? Four cases
Filled but never started — as good as it gets. Just your tank has petrol in it, and so the job is emptying that tank and purging the system where your car stands. This situation can only really take place at a forecourt: anywhere else, the car got there by being driven.
Ignition on, or started for a moment. Petrol has come out of the tank and reached the fuel filter and your lines, because your system has been primed. Normally nothing more than draining, cleaning and seeing to the filter, so still easy.
Driven a few miles. Now your pump has spent those miles labouring on diluted fuel. How hard the vehicle was driven counts as much as how far, and the work covers the tank, the lines, the fuel filter and clean fuel through the whole circuit. Driving the children to Maple Cross Junior Mixed Infant and Nursery School is one sort of trip. Very different once more: a trip to St Albans, under 15 miles away, or some miles on the M25, under a mile from Maple Cross, where the engine kept running hard.
Knocking, a lumpy idle, smoke, a throttle gone soft: driven until it complained. That is the motor telling you its fuel has stopped acting like diesel. Leave it where it stops: a lay-by, a quiet street, the verge on Denham Way. Lasting damage is very rare if a vehicle is stopped quickly, and the drain and flush-through that still go first deal with it.
Maple Cross motorists and that petrol in a diesel myths they hear
It will not be fine. The myth: "Fill it the rest of the way with diesel and it will be." A bigger tank of the same mixture is all it gives, because topping up removes nothing. Percentage isn't how a diesel fuel system tolerates petrol, however much that advice presumes.
If anything, the opposite is true. Myth: "A modern diesel can cope with a bit of petrol." At higher pressure, through smaller parts: that's how a current diesel handles its fuel, so the lubrication matters more, not less.
This is the one that catches motorists. Myth: "If it starts and drives, there's no harm done." The driver of a petrol engine fed diesel normally stops, since it will not run, and the harm stops with them. Feed petrol to a diesel and it normally fires up, ticks over and pulls away like nothing has happened — all the while its pump wears. Running is not the same as fine.
An old fix for a different issue lies behind this one. Myth: "Add some two-stroke oil and drive the vehicle home." None of what petrol diluted is put back by it — and later, that tank still contains that petrol.
Once the engine has run, part of the petrol sits in the filter and the lines, not that tank — and your next start sends it right back through the pump. So the myth "drain the tank yourself and you're sorted" doesn't hold. Also, a can of petrol drained at the kerbside is genuinely dangerous.
Petrol in a diesel: how does it take place?
It is seldom carelessness, and no one does it on purpose. A diesel nozzle mostly will not go into a petrol vehicle, yet the narrower petrol nozzle goes into the filler of a diesel almost without resistance — so forecourts make this one error straightforward, and only in one direction.
When habit and the vehicle stop matching, it takes place. Courtesy car, hire car, or a motor that's new. Two cars on one driveway, one petrol, one diesel. The pumps in a different order on a well-known forecourt. A rushed fill en route to Rickmansworth with a train to catch. The first fill-up in a diesel Volkswagen Golf after years of driving petrol is precisely the moment it happens. With rain, a call coming in, or a car full of children to deal with, the hand simply does what it always has.
Maple Cross people: how to avoid petrol in a diesel next time
- The label is what counts, so check the pump instead of the colour: in the UK unleaded handles are normally green and diesel black, but not on each forecourt.
- The first fill in a new motor is the time to check the filler flap — on it, or on the cap, many cars state which fuel to use.
- A coloured fob or a sticker on your diesel's key does more than any amount of meaning to remember, in a home with one of each.
- Say it before you lift it. On the first fill in a new or hired car, say "diesel" aloud before you take the nozzle off the petrol pump. It sounds daft and it works.
- Whilst you're thinking about something else, this is an easy mistake to make — so put the phone away.
- A misfuel inhibitor helps, up to a point. Some diesels come with a filler built to refuse 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.
- As soon as you realise, stop: less petrol in the tank means a weaker blend. What to do next doesn't change, though — still do not fire it up.
Put petrol in a diesel in Maple Cross already?
Then the order of things is short. Do not start the vehicle, and do not switch your ignition on. If you are still at the forecourt — BP or anywhere else — ask the attendants to help you push it clear of the pump. Phone 0333 366 0103 next, with three facts — the fuel, the approximate volume, and if it has run.
AdBlue, not petrol? Then say so. Corrosion and deposits, not lost lubrication, make it a different issue — Maple Cross has a page all for it.
Maple Cross petrol in a diesel jobs: why one costs more than another
Four separate tasks lie behind the four scenarios above — which is why there is no fair single price. Which of them you're in is chiefly what shifts the cost. Where your car is matters too, and whether a van can safely reach it, after the ratio of petrol to what the tank takes.
That is why we ask three questions before costing rather than after: what went in, how much, and whether it's run. The answers turn a range into a straight figure.
About Maple Cross, briefly
Maple Cross is a village in Hertfordshire, situated near several lakes and water features, with an elevation of around 48 metres. Maple Cross lies approximately 18 miles west of London and 11 miles southwest of St Albans, near the villages of West Hyde and Mill End. Maple Cross has a population of around 1338 people, predominantly living in semi-detached housing. Maple Cross is also close to Horn Hill, which forms part of its wider landscape.
Maple Cross and Hertfordshire: where our fuel drain cover runs
Petrol in diesel calls in Maple Cross — part of the WD postcode area — go to vans that likewise cover the spots round it, West Hyde, Horn Hill and Mill End included. We drain where the car is — your own driveway, a lay-by, a supermarket car park, a forecourt — so it never needs to come to us.
At the petrol pump in Maple Cross, still?
Then you are in the best position there can be. Keep it off. Ring.