Put Petrol in a Diesel Car in The Marsh? Don't Start It
Petrol in Diesel drains and flushes wrong-fuelled cars where they sit, on the forecourt, by the roadside or on a private drive, throughout The Marsh and the remainder of Herefordshire. The very first thing to do is not to fire up the engine. While the motor has not been started and the petrol is still in your tank, a tank drain is nearly always all it requires, and the next few minutes decide that, not how much got in. Just one call to us will be enough: we shall show you what happens after this. Do that first.
Petrol in a diesel: what to try next
- Never start the car. Started all the same? Then don't rely on it. Diesel in a petrol car generally cannot run, so the driver stops and the damage ends with them. Petrol in a diesel? It starts. It ticks over. It moves off fine, for a couple of miles. Drivers get that confused. It is not all right — your fuel system is wearing down every mile you do.
- Leave the car's ignition be also. Diesel performs two tasks: it combusts, and before it combusts it protects that high-pressure pump and those injectors. Petrol does the first and not the second. Turning your ignition on is usually sufficient to prime that system, which draws this petrol out of that tank then into just those components.
- Topping up clears nothing. It hands you a bigger tank of the same mix, because a diesel fuel system won't handle petrol by percentage the way that guidance assumes — so do not tip diesel on top to weaken it. Octane is immaterial too: super unleaded is petrol.
- Wait where you are if you sensibly can. A motor that has never moved is the easiest one to sort out, and our team would much rather travel to a tricky spot than have it started. If you are parked on the verge on Osborne Place, put those hazards on then keep the vehicle there.
- Before you ring, gather your whereabouts. Anything next to you with a sign on it, plus a postcode starting HR6 8 — that is what decides whether the technician turns up or circles.
- Phone 0333 366 0103. Tell us what went in, about how many litres, plus whether the engine has fired. Those three facts shape the full visit.
Pump-side drains for petrol in a diesel
Most of the work begins at a forecourt, which means a good portion of it is done at one. Our technicians work on petrol station forecourts routinely, with the owner's consent, and so if you're still at Leominster Service Station that's usually where this drain takes place.
Nowhere other than a garage can it be spotted with the motor still cold. Fuel pulled out of that tank and through the fuel filter, right to your high-pressure pump, is what occurs when your engine is switched on and the vehicle is moved to where it is now: the car park, the private drive or the lay-by, everywhere other than the forecourt. So the flush takes in your filter and the fuel lines as well as the tank. That is still not a disaster, and our engineers sort it out where the vehicle sits. What settles it is whether the key was reached for in the seconds after your receipt was read.
Staff will usually chip in pushing it clear of the pump, which lets the next driver get through. Accept the offer. Shifting it four spaces doesn't warrant cranking it.
The Marsh and the villages near it
The Marsh is a residential suburb, and our team go out to it and to the areas around it on those same rounds: Leominster, The Broad, Newlands, Ryelands and Barons Cross.
Not on the list? That says nothing. The names above are just the nearest few, and the majority of places in Herefordshire have a page of their own somewhere on this site. Guessing is the mistake to resist, especially on the boundary or anywhere your phone gets lost. Call us to ask.
Check this map for the area included on this page. Your car does not need to come to us. We operate across the lot — kerbside, forecourts, driveways, car parks.
Nothing warns you, as from the driver's seat there's nothing to be warned about. The diesel Nissan Qashqai will have seemed perfectly ordinary on the way back from Leominster Primary School, and they all do — which is the snag with petrol in a diesel instead of the reverse. Diesel in a petrol motor usually refuses to run, stopping the driver and stopping the damage with them. Petrol in a diesel fires up, idles, drives off as though nothing had happened, and all the while your pump does its work without the protection its fuel is supposed to supply. Tell us roughly how far, and how hard. The harder matters more.
Leave it there overnight. Call us next morning. Nothing about a diesel Ford Focus parked in the car park outside The Hop Pole degrades as it stands, tank of petrol or not, and this job stays an easy one right up until the moment it gets taken home. The query our engineers arrive with is about the run there: a cold engine over a short run is where petrol ignites least well, and whatever fails to burn can work its way past the rings into the oil.
Why we are direct about not driving on: the pump sits upstream of your injectors, and so whatever a wearing pump gives off travels onward with your fuel. Leave the Mercedes A-Class near Leominster Community Centre then ring us.
Knocking, a lumpy idle, white smoke, a throttle gone soft. That is a misfilled diesel Citroen C3 telling you what's wrong. Turn off where you have stopped, close to The Forbury Chapel or anywhere else, and do not start the car to find a better spot.
Drain it and put clean diesel in — that's the suggestion you will get, generally from somebody confident, and it is half right. Do precisely that to a diesel Audi Q5 by Leominster Priory - Scheduled Monument and it would start, which is what makes the tip sound reasonable. What happens next is the issue: the motor at once draws the petrol left waiting in the filter and the feed lines straight back through your pump, as draining a tank does nothing about fuel that has already left it. Phone us instead. Our engineers flush your system and take the filter off where your vehicle has a serviceable one, which is the difference between the car being repaired and the vehicle merely starting.
The Marsh: stuck where you pulled up
Not everybody gets the chance to pull in somewhere suitable. If you realised after setting off and ended up by the verge of Ridgemoor Road, or at a lay-by somewhere with your hazards going, that's a common call for us and not a rare one.
Out of the vehicle when it's not sensible to wait there, beside it if it is. It will frequently oblige. A diesel running on petrol limps along quite willingly, and that's the problem: start it up to reach somewhere better and that mixture goes further into the system with every mile covered. Our van heading to a tricky place is no bother for us, and it is far better for the vehicle than carrying on.
Driven it already? Stop, and check below
Here is where the M50 comes in, under 25 miles from The Marsh. A drop in power, an uneven idle, smoke: those are the signs when they come, rather than a tidy stop — and a misfilled diesel will frequently take you onto it and some way along before anything feels wrong at all.
The first sensible junction is the one to take. Turn off there, and leave the restarting alone. Suppose the worst of that on a long run. Anything near the under 15 miles to the nearest city, and the petrol has been through the filter, through your pump, through the injectors. Say so when you ring. What our engineers bring differs.
A bit about The Marsh
The Marsh is a suburban area situated on the riverside in Herefordshire, with an elevation of 72 metres. The Marsh lies approximately 12 miles from Hereford and 122 miles from London, making it a relatively accessible location. The Marsh is characterised by its semi-detached housing and is near to other places such as Leominster and The Broad. The Marsh has a population of around 3807 people.
What follows when our engineers arrive with you in The Marsh
- Three things get checked before any quote — the fuel that went in, the amount, and if anything has been run since. Each answer alters the work.
- Away flows the contaminated fuel.
- Our technicians purge the fuel lines and clean the filter, so what's left in the fuel system isn't what started the trouble.
- We put new diesel in and prime your system.
- It's fired up with fresh diesel in it, and we make sure that it's running properly.
At that point it's ready to drive away. Lasting damage is very rare when it has been noticed soon, and since everything is done where the car is, it never has to go to a garage.
The Marsh AdBlue removal is a distinct matter
If what went in was AdBlue rather than petrol, the first instruction is unchanged — don't crank it — yet the fault isn't. Diluted diesel, and no protection left for the system that depends on it. That is petrol. Corrosion and deposits are what a diesel tank gets instead, as AdBlue is urea dissolved in water.
Both are ours. There is a separate The Marsh page for AdBlue removal, with the detail on it — including the reasons it usually turns out to be the worse of the two.
What a petrol-in-diesel drain will cost around The Marsh
What changes the figure is listed below, since the job is not one job and we cannot truthfully put a single figure on this page.
- Has it been started or driven? Nothing else counts for as much.
- The tank's capacity, set against how much of the wrong fuel got into it.
- Whether it is unleaded or AdBlue.
- Where the car is, and whether a technician can sensibly get to and work on it.
Tell us what the car is, how much went in, and whether your engine has run. A straight answer comes back, not a range. For the vehicle at home that is going nowhere and is not pressing, is fine too.
Petrol in diesel queries from The Marsh drivers
I am on a forecourt in The Marsh. Can you drain the vehicle on the spot?
A large part of this work takes place there, so yes. Routinely, provided the site agrees: Shell, plus every other forecourt nearby. Say on the phone where exactly you have stopped. Whether we can work in that place is something we answer there and then.
A couple of litres of petrol in a diesel — too much?
Litres are not the measure. Ratio is, and a lot more than either, it counts if anything has been run. What decides how much work is required is whether that mixture has been sucked through your fuel system — since although five litres in an almost empty tank is a different matter from five in a full one, either way that is the query.
Already driven it with petrol in the diesel? What now?
Somewhere safe, then stop, then switch off and leave it off. Driving takes the issue along — out of the tank, into the pump and injectors. People fear it a good deal more than the recovery rate warrants, mind. The one truly valuable thing left to you isn't restarting the car.
Fuel drains and manufacturer warranties
It is not an alteration, and so a drain and flush carried out correctly doesn't void a manufacturer's warranty. What's likelier to start an argument is a diesel that has been run on petrol. One more reason for your engine to remain off.
Can I just add two-stroke oil and drive home?
No. It belongs to a different fault from a separate era, and petrol has weakened something no oil of that kind replaces. Petrol stays in that tank afterwards, whatever else goes in, and your pump gets no reprieve from it.
Main dealers and petrol in a diesel
Not at all. We drain and flush the car wherever it is, so there's no need to take it to a dealership.
Standing next to it?
Your engine remains off.
Already driven it? Then pull over somewhere safe, turn off, then let the vehicle stay that way. Cold, parked, going nowhere: that is the best position to be in. People fear this much more than they need to.
Draining misfuelled vehicles, The Marsh and the rest of Herefordshire, wherever they are. Roadside. Forecourt. Home.