Petrol in Diesel Engine

[mbp]

I own a 2006 Octavia 2000cc 105BHP Diesel Estate.

I put 24 litres of petrol in the tank before realizing my error. Topped up with 20 litres of diesel to try and mimimized the petrol content. Engine started and I drove home. Engine stopped after 10 miles. Called Emergency Services who pumped the tank out and put in small amount of diesel. Car started so I drove to nearest garage and filled up with more diesel. Car seems OK, but is there anything I should check before I drive it much further?

A rather scary and stupid mistake.

Regards, MBP

[moley]

You should have called the breakdown service to pump out the petrol before you started the car, then filled it up with diesel.

[Tech1e]

Yeah damage is done now. Might be alright but you might well find you have injector issues before long only time will tell.

[Guest westallc]

why would you carry on after knowing you filled it with 24litres lol it wont go away if you add the same diesel lol you should have called the breakdown att hat point imo

[mannyo]

A small amount of petrol would have been ok, but half a tank is taking beyond the point where it will make no difference.

[Captain Kremen]

I dunno, I filled my diesel up with a tank of petrol once, & it cut out like yours did once the diesel had got out of the filter casing. Someone told me they are designed to cut out like that (?). I drained it & filled it back up with diesel,and it has been fine for the last 40,000 miles!

Edited 12 December, 2010 by Captain Kremen

[Tech1e]

Designed to cut out?

Err you mean a diesel wont run on petrol so stops..lol

Problem is a diesel system uses the fuel to lubricate parts of the pumps as its a heavy oil. Petrol strips the oil out and friction builds up, bits of metal come off and go around the system. Sooner or later a bit of that metal will get somewhere it shouldnt be or a pump will wear out.

[vRS Joe]

My mother filled up her car (not a Skoda) from 1/4 to full with petrol then drove 250 miles before complaining it was "slower than normal". Sure enough the tank stank of petrol. We simply drained it, topped it up with diesel mixed with a litle oil to aid lubrication.

Now and again for the next year or so we put oil in the derv, though we have stopped doing it now.

50000 miles later it runs absolutely fine, no parts changed, no smoke, no nothing!

That wasn't the first time she did it either, I suspect it won't be the last!

I wouldn't worry!

[rwbaldwin]

My mother filled up her car (not a Skoda) from 1/4 to full with petrol then drove 250 miles before complaining it was "slower than normal". Sure enough the tank stank of petrol. We simply drained it, topped it up with diesel mixed with a litle oil to aid lubrication.

Now and again for the next year or so we put oil in the derv, though we have stopped doing it now.

50000 miles later it runs absolutely fine, no parts changed, no smoke, no nothing!

That wasn't the first time she did it either, I suspect it won't be the last!

I wouldn't worry!

I doubt it was a PD as the injectors are sensitive to petrol in diesel and are damaged very easily.

A non-PD will suffer much less and performs poorly because the petrol will lower the cetane rating. I do doubt the 75% petrol claim though.

[rwbaldwin]

One thing I would do is change the fuel filter after a couple of days. That much petrol in tank will tend to release any crud stuck to the inside of tank.

[xman]

I doubt it was a PD as the injectors are sensitive to petrol in diesel and are damaged very easily.

A non-PD will suffer much less and performs poorly because the petrol will lower the cetane rating. I do doubt the 75% petrol claim though.

That is completely incorrect, the chances of damage to a PD engine is very small - the critical parts on a PD injector are external and lubricated with engine oil. The low pressure lift pump in the fuel tank is similar to the fuel lift pumps in the petrol engines and wont be damaged

The engines that suffer critical damage are Common Rail engines where the high pressure pump feeding the rail suffers damage due to lack of internal lubrication. Metallic debris then gets into the injectors which, being pilot operated with ridiculously miniscule drilling get blocked.

All diesels will stop once the petrol coming through exceeds a certain level as it wont ignite. An inbuilt safety mechanism!

Dont worry MBP, you should be fine.....thank your lucky stars you didnt have the "latest tech" CR engine!

Edited 12 December, 2010 by xman

[Tech1e]

That is completely incorrect, the chances of damage to a PD engine is very small - the critical parts on a PD injector are external and lubricated with engine oil.

So the pump inside the injector and the internals of the tandem pump are lubricated with engine oil?

Best go back and do the diesel course then, oh and fish the knackered injectors out of the scrap ive changed, whoops.

[Minimoke]

If it was a CR diesel I think the injection system would be guaranteed to be completely wrecked as the whole system works at incredibly high pressures and relies 100% on the lubriication properties of the diesel fuel.

A PD diesel MIGHT be a bit more forgiving of a drop of petrol than a CR because parts of the system rely on external oil. But as has been pointed out earlier the injectors and pump internals still rely on diesel lubrication.

Personally I would fear the worst bearing in mind the high concentration of petrol but you might be lucky as it is a PD. Only time wil tell.

But I can't understand why, if you knew what you had done, you still drove away from the garage. Getting the AA to pump out the tank/system might have been a pain in the backside, but the cost of that is orders of magnitude cheaper than a complete new injector system (or worse).

Edited 13 December, 2010 by Minimoke

[dekka48]

If it was a CR diesel I think the injection system would be guaranteed to be completely wrecked as the whole system works at incredibly high pressures and relies 100% on the lubriication properties of the diesel fuel.

A PD diesel MIGHT be a bit more forgiving of a drop of petrol than a CR because parts of the system rely on external oil. But as has been pointed out earlier the injectors and pump internals still rely on diesel lubrication.

Personally I would fear the worst bearing in mind the high concentration of petrol but you might be lucky as it is a PD. Only time wil tell.

But I can't understand why, if you knew what you had done, you still drove away from the garage. Getting the AA to pump out the tank/system might have been a pain in the backside, but the cost of that is orders of magnitude cheaper than a complete new injector system (or worse).

I once put a small amount (about a litre) of petrol in my previous Octavia 2.0 PD. It was a nearly empty tank so I topped up with about 40 litres of diesel. Then, in a bit of a flap, called the recovery and when it arrived the driver said it would not be a problem in such a small quantity so I drove home very worried. The car drove fine but I still went to my local dealer the next day and had everything pumped out, fuel filter replaced and the lines cleaned (at least I think that's what they did. Bloke in the garage said any damage was unlikely. I haven't had the car for a few years but I still see it around now and then and I sincerely hope no damage surfaced when under new ownership.

Suffice to say I was so rattled by this that when I bought my Scout I purchased one of these:

http://www.stopdieselmisfuelling.co.uk/

And it is a doddle to fit and use. And well worth the £30 or so it costs.

[darrenw]

It happens more that you might think.

I nearly did it with a hire car in Florida. It didn't help that unleaded was black and diesel was green.

[Justa]

i put about £10 worth of petrol into my Ibiza FR TDI a few years back - just filled it up with diesel and it was fine

In fact I always thought it seemed to go a bit better after that !

[Mac1961]

Back in the 70's, diesel fuel tended to 'freeze' (went to a jelly-like substance and wouldn't flow) at low temperatures. Additives were available to counter-act this, but a common practice was to add about a gallon of petrol to a tank of diesel and it did the trick. Never heard of any engines being damage as a result. Thankfully, diesel fuel now comes with the additives already added so there's no problems.

Mac

[themacster]

I filled a diesel Peugeot 406 (first diesel I ever had) with petrol, about fifth of a tank before I realised, topped up with diesel and it was fine. I also felt it ran better with the petrol in it!

[Minimoke]

Suffice to say I was so rattled by this that when I bought my Scout I purchased one of these:

http://www.stopdieselmisfuelling.co.uk/

And it is a doddle to fit and use. And well worth the £30 or so it costs.

Dekka - does it allow you to fill up properly?

I purchased one of the Caparo devices which is similar, but had to stop using it. The problem I found was that the device does not let the pump nozzle go fully into the tank neck. The result is that I could never get the tank more than half filled before the pump cut off tripped.

The other similar device on the market (Diesel Key - the one that is Thatcham approved) is not recommended for use on the FL Octavia, I believe for the same reason noted above. I recently exchanged a series of emails with the actual designer and he told me that unfortunately the manufacturer is not intending to make a version suitable for the FL Octavia available any time soon.

Edited 14 December, 2010 by Minimoke

[mikey vrs]

I actually put some petrol in my diesel this week as it was freezing up in the -16 tempratures This was a 14 year old transit van with a old style diesel engine! Only time will tell if you have done any damage to your car,why you started it knowing you had put that amount of petrol in is madness.

[bobbie]

As most have said, if your car is a PD, then you may have got away with it.

If its a CR , consider it to be now destroyed ! the cost of repair will be more than your cars worth , but you would have found out by now.

In either case though, why o why did you start the engine knowing what you had done ?

Lady luck is definately with you !!!

[Golf-Fiend]

http://www.stopdieselmisfuelling.co.uk/

And it is a doddle to fit and use. And well worth the £30 or so it costs.

Amazingly it also upgrades your Audi to a BMW just by adding the wrong fuel and the cost of £30 quid!! A bargain! (read: Dealer Misfuel Leaves Audi A4 Worse for Wear! )

[dekka48]

Amazingly it also upgrades your Audi to a BMW just by adding the wrong fuel and the cost of £30 quid!! A bargain! (read: Dealer Misfuel Leaves Audi A4 Worse for Wear! )

Oooops! Copywriter getting a bit carried away there!