Petrol in diesel fuel tank - what should I do?
Discussion
I filled my my 2014 Mercedes E220 CDI with petrol. About 55 litres of petrol in a 59 litre tank.
First thing I did was blast off down the motorway, got about half a mile before the most god awful explosions started coming from the exhaust.
The car lost power and luckily there was a slip road off in a few hundred yards all downhill. All the warning lights came on and the engine stopped, luckily the auto seemed to switch itself into neutral. I came to a halt at the side of the road under the motorway just off the exit of the roundabout. I switched off the ignition still none the wiser. Left it a couple of minutes and restarted the car. The engine ran roughly then all the lights were back on with a message along the lines of 'Don't switch it on again'. After that the key wouldn't do anything.
A quick call to Mercedes Mobilo to come and get me, a lift back to the dealer with the car and a pleasant wait with coffee and papers resulted in the diagnosis and a £700 bill. The car was ready a few hours later and I returned with the B Class they loaned me.
The 220 has been perfect ever since, even been on a high speed thrash across Europe to Italy and back.
Bloody expensive tank of petrol though...
First thing I did was blast off down the motorway, got about half a mile before the most god awful explosions started coming from the exhaust.
The car lost power and luckily there was a slip road off in a few hundred yards all downhill. All the warning lights came on and the engine stopped, luckily the auto seemed to switch itself into neutral. I came to a halt at the side of the road under the motorway just off the exit of the roundabout. I switched off the ignition still none the wiser. Left it a couple of minutes and restarted the car. The engine ran roughly then all the lights were back on with a message along the lines of 'Don't switch it on again'. After that the key wouldn't do anything.
A quick call to Mercedes Mobilo to come and get me, a lift back to the dealer with the car and a pleasant wait with coffee and papers resulted in the diagnosis and a £700 bill. The car was ready a few hours later and I returned with the B Class they loaned me.
The 220 has been perfect ever since, even been on a high speed thrash across Europe to Italy and back.
Bloody expensive tank of petrol though...
"My friend" once had a VW Golf 2.0 Tdi, 2014 model with 20,000 miles. Filled with 6 litres of petrol before "my friend" realised his mistake. Topped up to the brim with Diesel and it ran fine for a while. 1,100 miles later the diesel pump failed without any warning. £750 in parts and £400 labour including a tow. "my friend" was also told that the injectors were damaged, though he drove it for another 3 months without any breakdown before the lease ended and the car was returned.
Update from last night: another 500 miles, and back home now. All petrol is out of the system as the last fill-up was from nearly empty. Everything fine so far. Fuel consumption is back to normal (down from approximately 15% better with the accidental petrol/diesel mix).
I'll report back if anything breaks. It gets a lot of use (12,000 miles in the last seven weeks), so any consequences ought to manifest soon.
Findings based on personal experience (so far) are that 33% petrol in a Sprinter 416 won't break it; it improves the fuel consumption considerably; and it smokes much less when pulling hard on full throttle.
I'll report back if anything breaks. It gets a lot of use (12,000 miles in the last seven weeks), so any consequences ought to manifest soon.
Findings based on personal experience (so far) are that 33% petrol in a Sprinter 416 won't break it; it improves the fuel consumption considerably; and it smokes much less when pulling hard on full throttle.
3528 said:
3528 said:
Long story short: currently on autoroute in Normandy. Sprinter 416 plus car trailer. 50 litres diesel; 25 litres petrol. Running absolutely fine. I'll report back with any notable developments.
Just diluted with another 12.11 litres after 66 miles. 24.7mpg, incidentally. It's never anywhere near this good, especially with the trailer. 
h to start, smoked like a bd but it went like buggery. I think most of the problem starting it was that it was in the middle of winter and obviously the petrol/diesel mix would have preferred a warmer climate
So my partner put 20 pounds worth of unleaded petrol into a empty tank of our freelander 2007 diesel car an only realised when the car started to drive sluggish he manage to get home from the garage which is about a mile away. I contacted the garaged who confirmed he had put in an played for unleaded not diesel so he drove it back an topped it to the brim with 70 pounds worth of diesel. Yesterday he drove over 100 miles an the car runs ok but struggles to start an that seems to be worse each time he starts the car.
I've spoke to a fuel draining company and they have said we need to pay for it to be drained an flushed through but I'm gutted we will waste so much diesel that he has put in ontop of the petrol.
Not sure what to do as some posts say to keep refuelling after so many miles an but what happens if your tank gets low will the petrol always be sitting ontop of the diesel and inevitably end up wreaking the fuel tank if you run the car to low.
Need help please
I've spoke to a fuel draining company and they have said we need to pay for it to be drained an flushed through but I'm gutted we will waste so much diesel that he has put in ontop of the petrol.
Not sure what to do as some posts say to keep refuelling after so many miles an but what happens if your tank gets low will the petrol always be sitting ontop of the diesel and inevitably end up wreaking the fuel tank if you run the car to low.
Need help please
Plastic chicken said:
Funnily enough, my mate & I were talking about misfuelling in the pub last night, because he'd recently done just that. He came up with this suggestion: why not fit petrol cars with a standard circular filler, and fit diesels with a triangular or oval-shaped one? Most garages have two diesel fillers to every one petrol at every pump, so one of the diesels could be retro fitted with a simple shape adaptor or a new nozzle to accommodate newer cars. It could be made impossible to fit your nozzle into the wrong-shaped hole, ooh-er missus.
It's not completely idiot-proof, but I couldn't think of a reason why that wouldn't work.
I have a foolproof system for making sure I put the right fuel in a car. If it's a petrol car, I pick up the nozzle with the green hose that is marked "Unleaded" and make sure the fuel residue around the end of it is quite thin and smells nice. It's not completely idiot-proof, but I couldn't think of a reason why that wouldn't work.
If I'm filling diesel, I use the nozzle with the black hose that is labelled "Diesel" and make sure the fuel residue around the end is thick, oily and smells horrible.
It's a foolproof method that hasn't let me down yet.
Dandan1719 said:
Need help please
You probably need a new car. Running petrol through a diesel engine will wreck the fuel pump, and you have ensured that the resulting debris has now been pumped through the entire fuel system. That will be very expensive to repair, and given the age of the vehicle I doubt it is economically sensible to repair it. Any slight hope you might have had of limiting the damage was lost when the driver decided to drive it home, and driving it back afterwards just compounded the damage. It would really pay you to have a talk about what to do next time the mistake is made.Hey this post is getting old ffs
So I... second time.... filled me vdub LT with green pump stuff. This time I forgot I wasn't in a mates runaround that drinks petrol juice.
Started it and got half mile before it started the jerking. A friendly soul came up and said would I like a push... being on a dual carriageway with a slip road not 5 metres ahead.
Siphoned out two thirds making myself sick in process with loads of 5litre bottles I could recycle using a clear tube and my mouth. Swallowed some... got some over me... head a bit light.
80 litre tank ... removed 60... and then topped up again but with the black juice this time.
Wouldn't start for two days. Ran battery down further. Think may have had a battery issue anyway. After 72 hours on a cold morning with jump leads the van started and billowed out plumes of smoke.
Was getting jumpy thinking of the bills that would arrive before me but think I should just clean it up a bit... give it new fuel filter and lines.
A ^friend^ said to open the diesel injectors to let any air that got locked in. I was trying to find some u tube video to guide my hands. But it started so I never got to continue with that. If anyone has any idea of how to do this and which bit or spanner i need then that would be an interesting diversion for this thread.
Thanks for the educational entertainment 🐝
So I... second time.... filled me vdub LT with green pump stuff. This time I forgot I wasn't in a mates runaround that drinks petrol juice.
Started it and got half mile before it started the jerking. A friendly soul came up and said would I like a push... being on a dual carriageway with a slip road not 5 metres ahead.
Siphoned out two thirds making myself sick in process with loads of 5litre bottles I could recycle using a clear tube and my mouth. Swallowed some... got some over me... head a bit light.
80 litre tank ... removed 60... and then topped up again but with the black juice this time.
Wouldn't start for two days. Ran battery down further. Think may have had a battery issue anyway. After 72 hours on a cold morning with jump leads the van started and billowed out plumes of smoke.
Was getting jumpy thinking of the bills that would arrive before me but think I should just clean it up a bit... give it new fuel filter and lines.
A ^friend^ said to open the diesel injectors to let any air that got locked in. I was trying to find some u tube video to guide my hands. But it started so I never got to continue with that. If anyone has any idea of how to do this and which bit or spanner i need then that would be an interesting diversion for this thread.
Thanks for the educational entertainment 🐝
Cannabeans said:
Hey this post is getting old ffs
So I... second time.... filled me vdub LT with green pump stuff. This time I forgot I wasn't in a mates runaround that drinks petrol juice.
Started it and got half mile before it started the jerking. A friendly soul came up and said would I like a push... being on a dual carriageway with a slip road not 5 metres ahead.
Siphoned out two thirds making myself sick in process with loads of 5litre bottles I could recycle using a clear tube and my mouth. Swallowed some... got some over me... head a bit light.
80 litre tank ... removed 60... and then topped up again but with the black juice this time.
Wouldn't start for two days. Ran battery down further. Think may have had a battery issue anyway. After 72 hours on a cold morning with jump leads the van started and billowed out plumes of smoke.
Was getting jumpy thinking of the bills that would arrive before me but think I should just clean it up a bit... give it new fuel filter and lines.
A ^friend^ said to open the diesel injectors to let any air that got locked in. I was trying to find some u tube video to guide my hands. But it started so I never got to continue with that. If anyone has any idea of how to do this and which bit or spanner i need then that would be an interesting diversion for this thread.
Thanks for the educational entertainment ??
It doesn't need anything - change the filter if it makes you feel better, but I never have and I am the self-appointed King of Misfuellers.So I... second time.... filled me vdub LT with green pump stuff. This time I forgot I wasn't in a mates runaround that drinks petrol juice.
Started it and got half mile before it started the jerking. A friendly soul came up and said would I like a push... being on a dual carriageway with a slip road not 5 metres ahead.
Siphoned out two thirds making myself sick in process with loads of 5litre bottles I could recycle using a clear tube and my mouth. Swallowed some... got some over me... head a bit light.
80 litre tank ... removed 60... and then topped up again but with the black juice this time.
Wouldn't start for two days. Ran battery down further. Think may have had a battery issue anyway. After 72 hours on a cold morning with jump leads the van started and billowed out plumes of smoke.
Was getting jumpy thinking of the bills that would arrive before me but think I should just clean it up a bit... give it new fuel filter and lines.
A ^friend^ said to open the diesel injectors to let any air that got locked in. I was trying to find some u tube video to guide my hands. But it started so I never got to continue with that. If anyone has any idea of how to do this and which bit or spanner i need then that would be an interesting diversion for this thread.
Thanks for the educational entertainment ??
You'd have saved yourself a load of bother if you'd just called out a misfuelling place, paid your £150 and been on your way.
It doesn't need fuel lines.
It hasn't knackered the pump.
It doesn't need the injectors touching.
Just drain it and refill. Drive away.
Pump_Numpty said:
Evening chaps,
I want to post my misfuelling experience here after I read the advice from these very posts in a crisis, and duly ignored them.
A while ago I rented a diesel vehicle from a well known UK hire company who handed it over with just a sniff of fuel in the bottom of the tank. Annoyed at this but planning to do just a little bit of running around I headed for the pumps as a first port of call. In a bit of a flap, typical rush-hour queues at the pumps, running late and 2 attempts to get the filler on the correct side I proceeded to dump 25 litres of fuel into it, confident that would be enough for all the to and fro'ing I had planned.
Skip forward 15 mins / 8 miles and the barely run-in common rail oil burner is shuddering on the inside lane of the motorway ever so slightly. Weird. Few pumps on the throttle in 6th, yup, definitely not happy. 30 seconds later I'm smashing my palm into my forehead trying to beat out the nightmare image of the green pump handle hanging out the filler neck and the oblivious tool holding it, mind elsewhere...
Drop to 50mph, next slip is 2 miles further along the road and I think the AA card is in my wallet primed for its first actual use in 5 years of paying the subscription. She's not happy but makes it to the next forecourt somehow, spluttering away. Sod it, I'm dumping as much super diesel in it as she'll suffer (40l as it turned out), its a moment of desperation and I know it'll still be too rich but lets just 'see how it sounds' and take it from there plus I really need to get into town and meet these folks waiting on me.
For no reason at all I'm fully convinced lady luck owes me one here....
Stuck to 50-ish (<2000 rpm) on the remainder of motorway and its seemingly unaware of what I've done to it. Theres a very slight hesitation on pick up and it bogs down a tiny bit riding the throttle in 6th but its not putting up much of a complaint really, all things considered.
Journey completed, returned to my place and busied myself in forum messages and opinions by the end of which I was fully convinced I'd written the thing off and my only hope was to drain it, refill it and just pry that for some reason this fuel pump didn't need THAT much lubrication and hadn't suffered terminal damage. Half way out the door with a 2m length of bilge hose I thought, this is daft, its late, I have work in the morning, just phone them and explain whats happened after all thats what insurance is for. Back inside and Google 'thats what insurance is for'. Apparently not, read the t's & c's idiot, you're well and truly screwed. Full fuel system rebuild and you're footing the bill for the lot. No if's no but's and the media were quite delighted to supply the supporting evidence, if it was needed.
Next morning having barely been able to think about anything else all night I somehow arrived at the decision to bury my head in the sand. The facts were this:
- its working just now (cold and warm start confirmed, just half a crank each) , idles like new, and;
- it doesn't sound particularly unhappy. There's nothing clear from the outside to suggest an issue except the familiar whiff of a lighter fraction of oil in the mix when you open the filler cap and stick your nose in, but no one has a reason to do that surely?
So....We're boom or bust now. The back out route was 50 miles ago right? I've got a couple more jobs to do, I dont have time to drain it nor do I want to and I can definitely take it back like this, maybe even more dilute if I can free up a bit of space in the tank via some extra run time. Just get round a couple of jobs and back to the rental place. Couple of hundred miles max.
Proceed with plan, if you turn the innards to potting metal then so be it. You're in it now.
Jobs done. Melt down at every new rattle and crack from the interior along the way but all were false alarms. I even managed about 30 seconds of background radio before frantically shutting it off to hear a new imaginary whirring noise. Finished and importantly no discernible change in the symptoms. It doesn't seem to be getting worse and I'm all but done with it. Phew.
Next, time to wind out the brass neck: I'm not even diluting it further now before handing it back, I dont want to put another penny in this 4 wheeled indemnity someone could yet cash in against me and besides, I'm throughly enjoying the fact the finish line is in sight. I took a brain-dead risk and somehow its about to pay off and I'll be f#cked if I'm mitigating risk at this late stage in proceedings, that shipped sailed ages ago.
Handed the keys back to the guy too young for a suit. Felt like a right rotten sod. "Thats spot on mate, wish all customers returned them in the same state, not a mark on it". I managed to comfort myself with the knowledge that their offshore accounts could absorb this just fine whereas mine, firmly within the UK tax system, really couldn't. They don't run a risk free business and nor should they right? Sure, they must budget for unplanned maintenance and losses, nature of the game they are in....
So thats it. You told me not to but like a complete idiot I did it anyway and I promised myself at the time I would post the outcome on here given it was the forum I consulted most at the time and someone else is likely to be browsing this with a similar conundrum some time soon. By the way, if you are that person I thoroughly don't recommend doing the above, its incredibly stressful and for that reason alone its probably worth the £150-£200 to get it drained professionally and put right. You'll live longer.
In the end I calculate I was running about 35% - 65% mix in favour of diesel which is way too sweet by all accounts. But, based on my sample size of just one, if the engine is virtually brand new and not yours I conclude you CAN get at least a couple of hundred miles out of it and no follow up phone calls from the owners. Having looked into it a bit further I think it'll have put plenty of wear on the fuel pump but I doubt the injectors will have suffered any noticeable damage given all the subsequent nursing at <2000 rpm. True, the next user may have spent the subsequent 200 miles on the red line but I expect it just burned its way through most of it quite happily and was diluted down before arriving back at the depot and that was the end of that. The evidence I expect is now somewhere between the clouds and the ozone layer, either that or in a workshop vice with some spotty apprentice peering into it....
Yep, I've just done this and know everything you went through. Exactly same circumstances for me (I've owned a diesel and petrol vehicles at the same time and never made this mistake). Anyway, I filled up only 1/4 of a tank of a rental van with petrol. I filled it a few hundred yards from the rental place so praying it'll be fine. Why on earth do they not fit the pump filler device that stops people from doing it?!I want to post my misfuelling experience here after I read the advice from these very posts in a crisis, and duly ignored them.
A while ago I rented a diesel vehicle from a well known UK hire company who handed it over with just a sniff of fuel in the bottom of the tank. Annoyed at this but planning to do just a little bit of running around I headed for the pumps as a first port of call. In a bit of a flap, typical rush-hour queues at the pumps, running late and 2 attempts to get the filler on the correct side I proceeded to dump 25 litres of fuel into it, confident that would be enough for all the to and fro'ing I had planned.
Skip forward 15 mins / 8 miles and the barely run-in common rail oil burner is shuddering on the inside lane of the motorway ever so slightly. Weird. Few pumps on the throttle in 6th, yup, definitely not happy. 30 seconds later I'm smashing my palm into my forehead trying to beat out the nightmare image of the green pump handle hanging out the filler neck and the oblivious tool holding it, mind elsewhere...
Drop to 50mph, next slip is 2 miles further along the road and I think the AA card is in my wallet primed for its first actual use in 5 years of paying the subscription. She's not happy but makes it to the next forecourt somehow, spluttering away. Sod it, I'm dumping as much super diesel in it as she'll suffer (40l as it turned out), its a moment of desperation and I know it'll still be too rich but lets just 'see how it sounds' and take it from there plus I really need to get into town and meet these folks waiting on me.
For no reason at all I'm fully convinced lady luck owes me one here....
Stuck to 50-ish (<2000 rpm) on the remainder of motorway and its seemingly unaware of what I've done to it. Theres a very slight hesitation on pick up and it bogs down a tiny bit riding the throttle in 6th but its not putting up much of a complaint really, all things considered.
Journey completed, returned to my place and busied myself in forum messages and opinions by the end of which I was fully convinced I'd written the thing off and my only hope was to drain it, refill it and just pry that for some reason this fuel pump didn't need THAT much lubrication and hadn't suffered terminal damage. Half way out the door with a 2m length of bilge hose I thought, this is daft, its late, I have work in the morning, just phone them and explain whats happened after all thats what insurance is for. Back inside and Google 'thats what insurance is for'. Apparently not, read the t's & c's idiot, you're well and truly screwed. Full fuel system rebuild and you're footing the bill for the lot. No if's no but's and the media were quite delighted to supply the supporting evidence, if it was needed.
Next morning having barely been able to think about anything else all night I somehow arrived at the decision to bury my head in the sand. The facts were this:
- its working just now (cold and warm start confirmed, just half a crank each) , idles like new, and;
- it doesn't sound particularly unhappy. There's nothing clear from the outside to suggest an issue except the familiar whiff of a lighter fraction of oil in the mix when you open the filler cap and stick your nose in, but no one has a reason to do that surely?
So....We're boom or bust now. The back out route was 50 miles ago right? I've got a couple more jobs to do, I dont have time to drain it nor do I want to and I can definitely take it back like this, maybe even more dilute if I can free up a bit of space in the tank via some extra run time. Just get round a couple of jobs and back to the rental place. Couple of hundred miles max.
Proceed with plan, if you turn the innards to potting metal then so be it. You're in it now.
Jobs done. Melt down at every new rattle and crack from the interior along the way but all were false alarms. I even managed about 30 seconds of background radio before frantically shutting it off to hear a new imaginary whirring noise. Finished and importantly no discernible change in the symptoms. It doesn't seem to be getting worse and I'm all but done with it. Phew.
Next, time to wind out the brass neck: I'm not even diluting it further now before handing it back, I dont want to put another penny in this 4 wheeled indemnity someone could yet cash in against me and besides, I'm throughly enjoying the fact the finish line is in sight. I took a brain-dead risk and somehow its about to pay off and I'll be f#cked if I'm mitigating risk at this late stage in proceedings, that shipped sailed ages ago.
Handed the keys back to the guy too young for a suit. Felt like a right rotten sod. "Thats spot on mate, wish all customers returned them in the same state, not a mark on it". I managed to comfort myself with the knowledge that their offshore accounts could absorb this just fine whereas mine, firmly within the UK tax system, really couldn't. They don't run a risk free business and nor should they right? Sure, they must budget for unplanned maintenance and losses, nature of the game they are in....
So thats it. You told me not to but like a complete idiot I did it anyway and I promised myself at the time I would post the outcome on here given it was the forum I consulted most at the time and someone else is likely to be browsing this with a similar conundrum some time soon. By the way, if you are that person I thoroughly don't recommend doing the above, its incredibly stressful and for that reason alone its probably worth the £150-£200 to get it drained professionally and put right. You'll live longer.
In the end I calculate I was running about 35% - 65% mix in favour of diesel which is way too sweet by all accounts. But, based on my sample size of just one, if the engine is virtually brand new and not yours I conclude you CAN get at least a couple of hundred miles out of it and no follow up phone calls from the owners. Having looked into it a bit further I think it'll have put plenty of wear on the fuel pump but I doubt the injectors will have suffered any noticeable damage given all the subsequent nursing at <2000 rpm. True, the next user may have spent the subsequent 200 miles on the red line but I expect it just burned its way through most of it quite happily and was diluted down before arriving back at the depot and that was the end of that. The evidence I expect is now somewhere between the clouds and the ozone layer, either that or in a workshop vice with some spotty apprentice peering into it....
lahill said:
Only now it dawned on me it may cause an issue. Any advice wd be appreciated
Don't worry about it. Whatever damage it was going to do is now done. If it's still running OK now then it's safe to assume that the petrol concentration was not high enough to cause damage. Take it as a lesson to be more careful in future because that could potentially have been a very expensive mistake.Gassing Station | Home Mechanics | Top of Page | What's New | My Stuff