Put Petrol in a Diesel Car in Bissom? Don't Start It
With the tank still carrying the fuel and the motor not yet run, almost every job requires only a drain, so leave your engine off. That result is decided in the minutes straight after filling up, and not by the amount that went in. Across Bissom and the rest of Cornwall, Petrol in Diesel drains the vehicle and cleans it where it sits, whether by a roadside, on a driveway or at a forecourt. Our engineers shall explain what your next part is. Call us — that happens before anything else.
What to do now about petrol in a diesel
- Don't crank it. Started regardless? Then don't believe it. Diesel in a petrol vehicle normally won't run, and so the driver stops and the damage halts with them. Petrol in a diesel? It starts. It ticks over. It pulls away fine, for a few miles. Most people get that backwards. It's not fine — the fuel system is wearing every mile you do.
- Leave the car's ignition be as well. Diesel has two roles: it ignites, and before it ignites it lubricates your injection pump and the injectors. Petrol does the first and not the second. Flicking the ignition on is frequently enough to prime the system, which carries the petrol out of the tank then into exactly those components.
- That guidance presumes a diesel fuel system tolerates petrol by percentage. It doesn't. Tip diesel on top and nothing at all is removed; what you get is a larger tank of the same mixture. And no, the grade makes no difference — super unleaded is just petrol.
- Remain where you are if you sensibly can. A car that has never shifted is the easiest one to deal with, and we would rather come to an awkward spot than have it started. If you're pulled up on the verge on Bissom Road, turn those hazards on and leave it there.
- Keep your location prepared before you call. A postcode starting TR10 9 and whatever is next to you with a sign on it is the difference between a van showing up and the van circling.
- Ring 0333 366 0103. Tell us what got in, approximately how much, and if the car has fired. Those three replies decide the whole call-out.
On a forecourt: clearing petrol from your diesel
A good share of this work is finished at the pump, since that's where it usually starts. Still at Texaco? Then that's usually where it gets done. Station forecourts are routine for us, with the agreement of the site.
No place except a forecourt can it be halted with your motor still untouched. The few seconds between reading the till receipt and reaching for the keys settle how much needs rinsing. Everywhere other than the forecourt — a car park, a drive, a lay-by — your car was started and driven to get there, so fuel was pulled from your tank, through the fuel filter and into the high-pressure pump. That means the lines and the fuel filter need cleaning as well as your tank. It is not a disaster, and we can still deal with it where the car is.
Staff will normally pitch in pushing it away from the pump, which lets the next customer get by. Welcome the offer. Firing it just to shift four car lengths is not.
The difficult part is the bay, not your fuel. Motors either side of you, a trolley shelter behind, and now and then a height barrier on the way in that determines whether a technician can get to you at all — so when you phone from a car park like the one outside Lidl, say how much space there is round you and which way round the vehicle is. Those we attend frequently. Should there be no space to work alongside the diesel BMW 3 Series, it gets rolled with the engine off, and not out of fuss over a couple of seconds of running: priming occurs at every start, more of that blend exits your tank for your pump, and two shunts into a roomier space have silently made a bigger job of what was merely a motor standing still.
It will start. It will drive off perfectly well. That's the trouble, as a diesel on a weakened tank acts usually whilst wearing the parts its fuel should be lubricating. So no, do not risk the drive home from Kings Arms — leave the Mercedes C-Class and phone.
Diesel has to be viscous enough to seal the tightly fitted parts it passes through, and petrol thins it. That is the full mechanism, and it accounts for the ordinary Ash Wood call: a diesel Peugeot 3008 that went out there without fuss and came back down on power, lumpy at idle, perhaps smoking a little. A diesel injection system works hydraulically as well as chemically — it requires the fuel to hold pressure, not just to burn — so when the fuel weakens, pressure that should build then stay built starts bleeding past tolerances instead, and the motor gets a poorer, later, less even delivery than it was engineered around. None of that is the motor failing, which is the part worth hearing: it's the fuel no longer acting like diesel, and it stops when your fuel is corrected.
Strange places are where this happens most, and the reason is mechanical instead of careless: the slimmer petrol nozzle fits a newer diesel filler neck with almost no resistance at all. Filled up by Jubilee Wharf Gallery without thinking, in a diesel Kia Sportage you have had for two days? Phone us where you are. Hire and courtesy cars often get driven further before anyone realises, and distance is what decides how much petrol gets to the fuel injectors.
Put right and starting are not the same thing, and the difference is the system: our engineers flush it, and take the filter off where there's a serviceable one. Compare that with the confident advice you will get — drain the vehicle, refill with fresh diesel. Half right. Do precisely that to a diesel Vauxhall Insignia by Penryn Memorial Gardens and it will start, which is exactly why the advice sounds reasonable. Then the motor pulls the petrol left behind in the filter, and in the feed lines, straight back through your pump, since emptying a tank does nothing whatever about fuel that has already left it. Phone us instead.
Areas our team serve in Bissom
Bissom is a rural hamlet, and our technicians are out to the town and to the places near it on the same journeys: St Gluvias, Penryn, Tregew, Lower Treluswell and Flushing.
We do come. The names above are only the closest neighbours, and a page exists for the majority of places across Cornwall, and so an absence from the list is not an absence from the coverage. Ring us to ask instead of presuming — boundaries especially, and anywhere your phone might misread.
Check our map for the area covered on this page. Kerbside, forecourt, driveway, car park: all of it is territory our engineers cover, and none of it asks your car to move to us.
Kerbside call-outs around Bissom
Some people find no sensible place to stop whatsoever. If you realised after setting off and ended up on the verge beside Love Lane, or in a lay-by somewhere with the hazards on, that is a common call for us and not an unusual one.
Whether you wait beside the motor or step away from it depends on whether being nearby looks sensible. Never start it up to get to a safer place. It'll go — a diesel on petrol usually obliges — and each mile of obliging drags that blend deeper into your fuel system. We'll send our van to a tricky spot without any bother, and for the car that's a lot better than carrying on.
So you've driven it? Petrol in a diesel after a couple of miles
This is where the M5 comes in — over 50 miles from Bissom. It will frequently take you onto it, and some way along, before you feel a thing. Then it is smoke, an uneven idle and power draining away — not a neat stop. Wrongly fuelled diesels seldom give you one of those.
The next sensible exit is the one to take. Switch off there, then leave the restarting alone. Presume the worst of that on a long run. Anything near the under 10 miles to the nearest city, and the contamination has been through your filter, through the pump, through the injectors. Tell us when you call. What we bring alters.
All about Bissom
Bissom is a small coastal hamlet in Cornwall, situated near the city of Truro and close to the neighbouring settlements of St Gluvias, Penryn, and Tregew. Bissom lies at an elevation of 34 metres, overlooking the surrounding coastline. Bissom has a population of around 602 people, predominantly living in detached houses.
What our engineers do when we get to you around Bissom
- Three things get asked before any quote — your fuel that went in, the quantity, and if anything has been run since. Each answer changes the work.
- Away flows the tainted fuel.
- We clean the fuel lines and clear your filter, so what is left in the fuel system is not what started the problem.
- Our technicians put clean diesel in and bleed the fuel system.
- It is started with fresh diesel in it, and we confirm that it's running correctly.
That leaves it ready to drive away. Lasting damage is very rare when it has been spotted early, and since all of this is done where your car is, it never has to be taken to a garage.
A separate problem: AdBlue in a diesel tank in Bissom
The problem isn't the same, though the opening instruction is — don't crank it — if what went in was AdBlue instead of petrol. Diluted diesel, and no protection left for your fuel system that relies on it. That's petrol. Urea in water, AdBlue, and in a diesel tank that brings rust and residue.
Both are ours. There's a separate Bissom page for AdBlue removal, with the details on it — including the reasons it usually turns out to be the worse of the two.
What a petrol-in-diesel fuel drain will cost in Bissom
One figure wouldn't be fair here, as this is not one job. These are the things that change it:
- Started? Driven? Either answer counts more than anything else on this list.
- How much of the wrong fuel was put in, against how much your tank holds.
- The sort of liquid in the tank, unleaded or AdBlue.
- Access: the car's position, and whether working on it there's sensible for a technician.
Tell us what your vehicle is, how much got in, and if your engine has run. A firm answer comes back, not a range. If it is not urgent — the vehicle is at home and going nowhere — works too.
Petrol in diesel questions from Bissom drivers
Can you do a fuel drain at a petrol station in Bissom?
Yes — forecourts are where a fair share of this takes place. Consent from the site is the condition. Given that, a forecourt like Esso is somewhere we are often enough, along with the rest of them locally — so name yours on the phone and you'll hear if working there's possible.
How much petrol in a diesel is too much?
Litres aren't the yardstick. Ratio is, and much more than either, it matters if anything has been run. Five litres into a nearly dry tank isn't five into a full one, no. But both land on the same question in the end: has that mixture been sucked right through, or has it not?
Already driven it with petrol in the diesel? Now what?
Switch off somewhere safe, and keep it that way after you stop. Not restarting it is the single most helpful thing available to you now. Driving does move the trouble out of the tank and into the pump and injectors, yes, and it remains salvageable far more frequently than people assume.
Will a fuel drain void my warranty?
A manufacturer's warranty outlasts a drain and flush done to a good standard, which is no modification at all. An argument over a warranty is likelier to come from running a diesel on petrol — so leave it turned off.
Can I just add two-stroke oil and drive home?
No. Two-stroke oil is an old workaround for a separate issue and it doesn't replace what petrol has weakened. Petrol stays in that tank later on, whatever else goes in, and the pump gets no break from it.
Does petrol in a diesel have to go to a main dealer?
There's no need to bring it to a main dealer, as our technicians drain and clean the vehicle wherever it is.
Is your car still with you?
Leave the car switched off.
Driven it already? Then somewhere sensible, stop, switch off, and no restarting it later on. Cold, still, going nowhere: that is the best place to be in. Drivers fear this a lot more than they need to.
Across Cornwall and in Bissom: on-site fuel draining, at home or on the forecourt or at the roadside.