Should You Worry? Petrol in a Diesel Car in Salter Street
Less than you likely are, if it hasn't been started. Petrol sitting in a diesel tank does nothing to your motor until something pulls it through the fuel system — the ignition priming the pump, the starter, or driving itself. So the honest answer to the first query anyone around Salter Street asks, "have I wrecked it?", is generally no. Keep it that way: leave the motor off and phone Petrol in Diesel. What petrol actually does to a diesel, how to judge how far it has gone, and how to keep it from happening a second time: that is the rest of this page.
What petrol in a diesel does to the motor
Two tasks fall to diesel on its journey round a motor. Lubricating comes before burning; it does both. Made to extremely fine clearances, your injectors and your pump rely on your diesel flowing through them to keep their surfaces from wearing against one another.
Badly at the first, not at all at the second: that is petrol. Being less viscous than diesel, petrol strips away the lubrication a fuel system needs, leaving a pump running on that mixture to wear itself. It is also made to resist igniting under compression — the reverse of what a diesel needs — which is where you get the clattering.
Combined, those make the shape of the problem clear. It's circulation that does the harm, not contact. Petrol in the tank is a fuel problem. 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 Salter Street: how serious is it? Four cases
Filled up, never started. The best case there is. On a forecourt, and genuinely only there, the petrol is still limited to that tank — since anywhere else your car was driven to reach it. The task is emptying and purging on the spot.
A moment's running, or just the ignition on. With the system primed, your lines and filter now contain petrol that has come from that tank. That is normally still an easy task — a drain, a flush, and your filter dealt with.
Driven a few miles. Now the pump has spent those miles working on diluted fuel. Miles is only half of that; how hard it was driven matters just as much. Either way the work runs to the tank, the lines, the fuel filter and clean fuel through the whole system. Short trips, such as the school run to St Patricks Church of England Primary Academy, are one matter. A run as far as Birmingham, under 10 miles away, is a very different job. So is any miles on the M42, under a mile from Salter Street, where your engine has been labouring hard throughout.
It complained, and only then stopped: smoke, knocking, a throttle gone soft, an idle gone ragged. That's your motor telling you its fuel has stopped acting like diesel. Stop where you are — on the verge on Lime Kiln Lane, at the kerb, down a side road — and don't move it again. The fuel drain and flush still come first, and they take care of it: when a vehicle is stopped soon, long-term damage is very rare.
Salter Street motorists and the petrol in a diesel stories they hear
Myth: "Fill it the rest of the way with diesel and it will be fine." It will not. Nothing comes out when you top up — the tank just holds more of the same blend. A diesel fuel system does not tolerate petrol by percentage in the way that advice presumes.
Myth: a modern diesel copes with a bit of petrol. Rather, the opposite. Lubrication matters more on newer diesels, not less, because their fuel runs through finer components at higher pressure.
This is the one that catches drivers. Myth: "If it starts and drives, there's no damage done." Diesel in a petrol motor generally means a motor that won't run: the motorist stops, and so does the damage. While the pump wears, a diesel fed petrol normally starts, idles and drives away as if nothing has happened. A running engine doesn't mean fine.
An old fix for a different issue is behind this one. Myth: "Add some two-stroke oil and drive the car home." The petrol is still in your tank after that, and whatever it has weakened is not put back.
If the motor has run, part of the petrol is in the filter and your lines, not the tank — and the next start sends it straight back through your pump. So the myth "drain the tank yourself and you're sorted" doesn't hold. And, a can of petrol drained by the roadside is genuinely hazardous.
How petrol ends up: petrol in a diesel
A careless moment is seldom the cause, and nobody means to do it. The forecourt makes it simple: the petrol nozzle is the narrower of the two, and it slides into a diesel filler with almost no resistance, whilst a diesel nozzle mostly will not go into a petrol vehicle at all. So the error runs one way.
When habit and the vehicle stop matching, it takes place. A new vehicle, a hire car or a courtesy car. Two cars on one driveway, one petrol, one diesel. A forecourt you know, only with its pumps arranged differently. A train to catch, and a rushed fill on the way to The Lakes. Years of petrol cars behind you, a diesel Volkswagen Passat in front of you on the forecourt for its first tank — that is when. Throw in a back seat full of children, a phone call or rain, and habit wins.
Next time you fill up around Salter Street: preventing petrol in a diesel
- Not every forecourt in the UK keeps to green for unleaded and black for diesel, even if most generally do. Read the petrol pump's label; the colour is just a hint.
- Many vehicles state the fuel type inside your filler flap or on the cap, so check it on the first fill in a car you do not know.
- A coloured fob or a sticker on the diesel's key does more than any amount of intending to remember, for a home with one of each.
- "Diesel", aloud, before you lift the nozzle — every time a new or hired car needs its first tank. It sounds silly. It works.
- Whilst you're thinking about something else, this is an easy mistake to make — so tuck your phone away.
- Up to a point, a misfuel inhibitor helps: some diesels come with a filler designed to block a petrol nozzle, and aftermarket devices exist for the remainder. Count it as a backstop, and keep checking the petrol pump.
- The moment you notice, stop: less petrol in your tank makes a thinner mixture. What to do next doesn't change, though — still do not fire it up.
Petrol already in a diesel around Salter Street? Start here
The order of things is short, then. Leave it unstarted, with the ignition off too. If you are still at the forecourt — Murco or anywhere else — ask the staff to help you roll the car clear of the petrol pump. Next, 0333 366 0103. We'll ask what was put in, roughly how much, and if it's been run.
If it was AdBlue rather than petrol, say so. That is a different fault — corrosion and deposits rather than lost lubrication — and it has its own page for Salter Street.
Salter Street petrol in a diesel jobs: why one costs more than another
There's no fair single quote for this, since the four situations above are four separate jobs. What shifts your cost is chiefly which of them you are in. Where the car is counts too, and whether our van can safely get to it, after the ratio of petrol to what that tank takes.
Three questions come first, before quoting, rather than after — what was put in, how much, has it run — and this is the reason. Their replies are what change a range into one firm number.
About Salter Street and its setting
Salter Street is a locality in the West Midlands, situated near the riverside and surrounded by nearby places such as Warings Green, Illshaw Heath, and Earlswood. Salter Street has a population of around 512 people and is characterized by semi-detached housing. Salter Street is located approximately 8.5 miles from Birmingham and 93.4 miles from London, sitting at an elevation of 136 metres. Salter Street forms a small part of the larger West Midlands region, with its riverside setting providing a distinctive geographical feature.
Fuel drain cover across West Midlands, Salter Street included
Petrol in diesel call-outs around Salter Street — part of the B postcode area — go to teams that likewise cover the spots about it, Warings Green, Illshaw Heath and Earlswood among them. Our engineers drain where the car is — your own drive, a lay-by, a supermarket car park, a forecourt — so it does not have to come to us.
Salter Street: still at the pump?
Then you're in the best place there is. Keep it off. Call.