Adblue in your gas tank by mistake? We’ll get you back on the road
AdBlue is NOT a fuel additive and should never be mixed into your fuel tank – petrol or diesel. It needs to go into its own separate filler (usually with a blue filler cap). If you’ve mistakenly put AdBlue into the fuel tank it’s important to get it removed it quickly, or engine serious damage can occur. It’s not an easy DIY job, but our mobile units can get to you quickly and fix the problem.
Symptoms of AdBlue in fuel
What does AdBlue in fuel do to my engine?
AdBlue is a liquid that helps to remove nitrous oxide – a poisonous gas – from your car’s exhaust. It is used to clean exhaust fumes – it is definitely not a fuel additive. It mostly consists of ionised water and also contains urea, which is corrosive to fuel system pipes and seals.
Furthermore it is prone to crystallisation, clogging injectors and fuel filters – like the picture below. It will do expensive damage if not removed.
But provided you act quickly, it will be fine. We fix it on the spot so you can drive on without concern.
We bring specialist equipment to remove the wrong fuel safely – including flushing your fuel lines, filters, pumps and engine.
The procedure to drain wrong fuel, then re-set and re-start your car takes about 30 minutes.
Then you’re good to go.
We’ll give you fresh fuel so you can drive on. Once done, your vehicle will be just fine. Our mobile mechanic will be with you soon after you call.
Put AdBlue in the gas tank and driven it?
Your vehicle might go a short distance, depending on how much AdBlue has been put in. But as the contaminated fuel goes through the system it will do damage. It needs to be fully removed. There’s really no safe amount of AdAblue in petrol or diesel. If you’re not sure, call our hotline for sensible advice.
IIt’s very easy to our the AdBlue into the wrong filler without realising it – the fillers are usually right next to each other. Hundreds of motorists do it every day. If your car won’t start, or runs poorly after you added some AdBlue, call us and we will help you work it out .
Frequently Asked Questions:
Provided you act quickly, you’re very unlikely to suffer any serious damage. In the great majority of cases the vehicle will be up and running again as soon as we have drained the wrong fuel from the system.
It’s best if you haven’t started your vehicle, as that means there’s virtually no chance of damage. Even if you have started it, and maybe driven for a bit before noticing something was wrong, the chances of any lasting damage are slim. If you somehow managed to get home but then the car wouldn’t re-start, you’ll still be fine – but call us and get the wrong fuel removed as soon as you can.
However, the longer the wrong fuel remains in your tank, fuel lines, and engine, the more damage it will do. Left alone, it will gradually corrode rubber and plastic seals and tubes, and dissolve lubricating fluids.
It’s not advisable to continue to try and start the car, or to leave the wrong fuel in the system for any length of time. The simple fact is that petrol cars need petrol, and diesel cars need diesel. Anything else invites problems.
The small amount of unmixed diesel that remained in your fuel lines, and the slightly mixed fuel in your tank can carry you a short distance.
But once the petrol has traveled through the low pressure sender pump, then the fuel lines, up to and through the filter (which holds about a pint of fuel), through the hoses to the high pressure pump, thru the pump, into the common rail reservoir, and finally through the high pressure lines into the combustion chamber – that’s normally the exact point that the engine stops turning. This is what happens if you put petrol in a diesel vehicle. Petrol in a diesel system is bad news – it removes engine lubricants and corrode seals.
For these reasons, the because you likely want to finish your journey and continue using your car, the wrong fuel needs to be removed fully.
In the old days you could siphon petrol out of your fuel tank by sucking on a length of hosepipe but, besides the taste being quite evil, modern fuel tank designs make this unfeasible. It takes specialist equipment and expertise to do the job properly now.
The pictures here show the condition of two hoses that were used to empty misfueled diesel tanks. In both cases the mixture was more petrol than diesel. They show what happens to the plastics in your fuel line if exposed to mixed fuel over a day.
Left: After petrol/diesel mix was removed within an hour. The hose is still clear. Right: After petrol/diesel mix was allowed to remain in the system for a day. The hose shows black fluid, caused by rubber from hoses and seals dissolving in the petrol.
An environment agency licence is required to transport and store the mixed fuel we remove. It has to be securely and safely stored and is then ultimately re-refined and returned to the fuel supply chain.
Both are bad news.
In small quantities, and depending on the individual engine design, wrong fuel does different things in petrol and diesel engines. In the short term, petrol in a diesel will usually stall the engine. Depending on the mixture, it might just still run but with reduced power and sounding like a bag of spanners. Diesel in a petrol car will make it lose power, and run flat.
The worst case scenarios (and these are the WORST) are:
1) Petrol in a diesel pump will eventually damage the pump by corroding rubber an dplastic compoments and by removing the oily lubrication that diesel fuel provides – If you are unlucky enough to get a mix that just runs. You would also have to do a fair amount of driving with a heavy foot, and be oblivious to the car’s behaviour. The same issues would sooner or later require replacement of: common rail pump, piezo injectors, fuel lines, and high pressure fuel pump (this last operates at around 28 thousand PSI of pressure and is a highly engineered, relying on passage of diesel for its lubrication. Petrol does not lubricate – in fact it dissolves the oils in diesel – hence petrol is good for cleaning out oil stains. No lubrication means metal grinding on metal in a high pressure environment. The metal chafe is then drawn thru to the piezo injectors and ruins them as well, and on through the cylinder linings. This level of damage is rare, but horribly costly.
2) Diesel in petrol worst case scenario: the diesel will enter the cylinder and not burn, it will slide past the piston rings, into the oil sump and therefore the cars oil system. It will then increase the oil level to a point that could cause total engine failure (mangled rods, bent pistons, complete block failure) – or the thinning of the oil can reduce lubrication to the engine leading to a full seizure, big end failure, and/or ruined propshaft. This extreme damage would not be an easy thing to achieve – the car would be very low on power and not running right, you would have to do a good bit of driving in it to achieve the above. But it’s not what you want going on under the bonnet.
In both cases, the cost of removing the wrong fuel is tiny in comparison – and you will meantime be driving around in a car that actually works.
Sadly, some main dealers and “tooth sucking garages” look on misfuel cases as a winning lottery ticket. We’ve heard of people having their misfueled cars collected by main dealers from petrol station forecourts (cars that had not even been started, with only twenty pounds of wrong fuel added).
Entirely unnecessary replacements of very expensive components have then been carried out, at great expense and inconvenience. Hopefully, for the owners, the insurance companies picked up the tab. That’s fine until you lose your no-claims bonus, or it comes time to sell your car and have to explain why it needed so much major work.
It’s not economic for most garages to keep the specialist equipment we use to fully drain fuel from a car – many of them find it simpler and faster to call us to do the job.
It’s not recommended, but yes you can try it. If it’s just a small amount of wrong fuel in a full tank of the correct fuel – yes, you might be OK. You’ll find the engine tends to run poorly, and you may well see some dashboard warning lights which will have to be cancelled at a garage. Also when you next try to start the car with a cold engine, you may find the engine won’t fire.
Having said that, what you risk is corrosion of rubber hoses and plastic seals, and possible damage to fuel pumps and engine components. Any of those are going to be fairly expensive to fix. Some will be very expensive.
Trying to dilute the wrong fuel in your tank is at best a gamble. Occasionally it might work, but the cost of filling up the tank to the brim, added to the potential damage, makes it a potentially expensive one. But it is very much hit and miss whether you will even be able to get the car going, or keep it going, or re-start it the next morning.
We’re reminded of the old saying: if you’re in a hole – stop digging.
Calling us to fix the problem fully, and get you properly back on the road, is still likely to be your best, and cheapest option.
You probably feel like a muppet right now, but the best estimates suggest over 300,000 people a year in the UK put the wrong fuel in their car. The pumps look similar, you may be distracted, you are in a rush… there are plenty of very valid excuses you can give yourself. We do get a lot of calls from mums with toddlers in the car, but we also get plenty from professional gents who practically live for their cars. Not to mention the occasional tanker driver, ambulance, or taxi driver. And then there’s the boat owners who filled their huge tanks with the wrong fuel. So all we can tell you is you really are not alone.
We’ll do our best to deal with your problem very quickly, and let you put it in your rear-view mirror.
Neither. They blend very rapidly in the tank and it becomes a fairly even mixture, although they are different compounds. They both come from crude oil, and spend millions of years in the ground as part of one and the same thing. Technically speaking, the carbon chain in diesel is longer, but only refining separates them out, and once recombined they will mix and stay together until re-refined.
Yes, this used to be common winter practice until about the 1970’s. Petrol does indeed work as an ad-hoc winter fuel additive for diesel in remote and freezing areas, such as the midwest or Alaska.
However diesel engines in those days were low-tech brutes. They didn’t have things like the high-pressure pumps that make today’s diesel engines smooth and efficient. Today’s engines are snowflake prima donnas by comparison.
In any case, Winter Fuel Additive is now standardly added to our supplies of diesel by the refiners as early as September, so there’s no need to try the old home remedies.
Your Engine Management light can signal a variety of problems, small or large. The Engine Management computers themselves are not very informative: they either say – “no problem” or “problem”. Petrol in a diesel car will often confuse them. They are designed to regulate things like air and fuel flow, air pressure, exhaust pressure, exhaust temperature, ignition timing – all to give optimum performance, economy and emissions.
The wrong fuel throws all that complicated measurement and computation off. Some very intelligent engine management units will try to “adjust” to the contaminated fuel, and when they fail to do so (as they always do) they will throw up a fault code which or may not be accurate.
The vast majority of fault codes generated by a wrong fuel scenario are temporary – once the engine is getting the right fuel, they will switch off. It is very rare that a light stays on after a fuel drain and restart, but our specialist engineers tend to know any peculiarities there may be for your make and model and will give you the best advice for your circumstances.
No, you not need a new filter to correct the effects of misfueling. Some garages assume that the filter will be contaminated with condensed amounts of wrong fuel and thus continue to weep wrong fuel into the system. In fact a filter does not hold much fuel, and petrol and diesel certainly do not “condense”.
The filter is simply a housing with a cardboard/paper filament to catch solid debris. It also has a water trap to stop water going into the engine. It needs to be emptied on servicing, or by dashboard warning light sensor.
Diesel and petrol do not “sit” in a fuel filter. When a fuel drain is performed of a car to remove wrong fuel, the filter is a flushed (by pumping the correct fuel through the filter to purge it).
A note of caution: We’ve occasionally seen hyperinflated garage bills for replacing a fuel filter. In fact they cost a few pounds, and take a around 6 to 8 minutes to change.
This used to be possible, and on cars older than about 30 years it still is – if you don’t mind the taste of diesel in your mouth for a week. And older engines were more tolerant of bad fuel, so it was less critical that the wrong fuel was thoroughly removed.
But today cars have things like anti-syphon devices to stop the hosepipe reaching the fuel, and saddle-shaped fuel tanks with internal baffles which a normal hosepipe can’t get into.
It took quite some ingenuity and persistence to devise the specialist equipment we now use to do the job.
There’s also the problem of getting rid of the mixed fuel. It can’t be legally dumped down the drain, and it’s of no other use. We collect it in approved storage areas and then send it back to the refinery.
The symptoms of contaminated fuel are similar to wrong fuel – in fact wrong fuel is really just a type of contamination. The cure is the same: fully drain out the wrong or contaminated fuel from the tank and fuel lines and engine, do any engine management reset needed, and fill up with the correct fuel. e deal with all of these peoblams daily.
Yes. It can happen very easily because the fillers are usually next to each other. And many people have the mistaken idea that AdBlue is type of fuel additive. It isn’t.
Adblue is one third urea (acidic) and two thirds deionized water. That acid solution gets passed through your engine along with the fuel – with predictable results. Starting the engine will make the problem worse.
AdBlue helps to remove nitrous oxide – a poisonous gas – from your car’s exhaust. It is used to clean exhaust fumes. It works to convert nitrogen oxide emissions in the exhaust gas of diesel engines, into nitrogen and water. A particulate filter then further reduces solid particulates from the vehicle’s exhaust emissions.
Furthermore it is prone to crystallisation, clogging injectors and fuel filters.Fuel filters that have had AdBlue put through them decompose and fall apart, like cardboard soaked in water. It happens quite fast.
The acidic urea and paper particles clog up and attack seals, fuel lines and injectors. It needs to be removed quickly, preferably before the engine is turned on.
Check the fuel cap of the vehicle which should tell you exactly what fuel the vehicle takes. That should make sure you dont put the wrong fuel in your vehicle.
There are a few signs to look for that may mean you put the wrong fuel into your vehicle.
•The vehicle may not start
•You may hear sputtering or the vehicle may stall
•You may see black smoke coming from the exhaust pipe
•Your car may overheat
•Your car may lose power
Diesel fuel is a type of fuel oil that is used in diesel engines. Petrol is a type of fuel that is used in petrol engines.
Diesel fuel is thicker and has a higher cetane rating than gasoline. Cetane rating is a measure of a fuel’s ignition quality. Diesel fuel ignites more easily than gasoline, which is why it is used in diesel engines.
