urgent help needed - put unleaded into 335d!!!

[Cootehall]

I know. I'm a fool. So, having realised I'd started to fill with unleaded I stopped (tank already had initially around 1/4 of diesel). After considering my options (was late at night, kids at home with baby sitter) I decided to fill the rest of the tank up with diesel and drove 80 miles home without any evidence of problems. This morning started the car and went on a local journey, starting was a little sluggish but it did start and drove OK. My wife is due to drive 250 miles tonight in the car - Any reason why it shouldn't make the journey? 80% diesel, 20% unleaded mix still a problem?? Am i writing off thousands in a new engine here or coud I get away with it? car is late 2006, 15,000miles.

[Fox-]

Trade it in and buy a Hyundai i10 petrol. You cant be trusted with a grownups car

[Roger645]

Tell us the Reg so we can avoid it!

[noumenon]

DON'T DRIVE IT.

Info from the AA website:

Potential damage
Diesel fuel pumps operate on very fine tolerances and are lubricated by the diesel fuel itself.

Petrol in diesel acts as a solvent – it reduces lubrication and can cause damage to the pump through metal to metal contact.

Some fuel system seals can be affected by the compounds in petrol too.

The further the contaminated petrol goes in the system the more expensive the repair – it can be cheaper in more extreme cases to fit a new engine.

The newer common rail (or HDi) diesel engines are particularly vulnerable – if fuel contaminated by pump wear debris gets as far as the common rail system you may have to replace the low and high-pressure fuel pumps, injectors, fuel rail, line filters and the fuel tank too.

Many systems use a low-pressure electric pump in the tank or sender unit and this begins to work as soon as the ignition is switched on, circulating the contaminated fuel through the pump and rail – so it's important not to turn the ignition on.

Petrol in Diesel
If the car's still under warranty you should check with the franchised dealer regarding the correct remedial action – some manufacturers advise that seals and filters should be renewed even if the engine has not been run.

Modern diesel with common rail or unit injectors – if you've added any petrol at all then the car shouldn't be started and the tank must be drained.
Other diesel engines (not common rail or unit injectors)
More than 10% (5 litres in a 50 litre tank) petrol – Drain the tank and refill with diesel
Less than 10% petrol – Top up with diesel and run normally

[NickB12]

There are firms which specialise in draining incorrectly filled tanks. Whether you trust them to be thorough enough though.....

[adycav]

It still won't be as fast as the 335i you know...

[stevesingo]

I was in a hire minibus (Transit with common rail injection) and the driver put about 30lt of unleaded in the tank. Filled up the remainder with diesel so all in we had 40%UL 60%Derv.

It idled a bit lumpy but ran OK for the next 100 miles. Topped up with diesel again it ran better and was running perfect when it was handed back after a full tank of diesel had been used.

The key is to keep topping up the tank in order to dilute the mix a soon as possible.

No one is going to strip and inspect your fuel system for a little extra wear occurring due to a minor mishap.

Steve

[Johnbmw6]

Cootehall said:

I know. I'm a fool. So, having realised I'd started to fill with unleaded I stopped (tank already had initially around 1/4 of diesel). After considering my options (was late at night, kids at home with baby sitter) I decided to fill the rest of the tank up with diesel and drove 80 miles home without any evidence of problems. This morning started the car and went on a local journey, starting was a little sluggish but it did start and drove OK. My wife is due to drive 250 miles tonight in the car - Any reason why it shouldn't make the journey? 80% diesel, 20% unleaded mix still a problem?? Am i writing off thousands in a new engine here or coud I get away with it? car is late 2006, 15,000miles.

You'll be very lucky to get away with driving it, it should havew been drained without starting the engine....................... Good Luck and get shot of ASAP, before the bang.

[R5GTTgaz]

Get it mapped for 95RON.

[roofer]

80/20 won't hurt, get it down to 3/4 tank and top it off again.

Edited by roofer on Monday 8th September 23:36

[DSM2]

Keep it topped up daily to dilute ASAP.

[noumenon]

roofer said:

80/20 won't hurt, get it down to 3/4 tank and top it off again.

Edited by roofer on Monday 8th September 23:36

You know better than the AA?

[stevesingo]

noumenon said:

Info from the AA website:

Potential damage
Diesel fuel pumps operate on very fine tolerances and are lubricated by the diesel fuel itself.

True

noumenon said:

Petrol in diesel acts as a solvent – it reduces lubrication and can cause damage to the pump through metal to metal contact.

True

noumenon said:

Some fuel system seals can be affected by the compounds in petrol too.

True

noumenon said:

The further the contaminated petrol goes in the system the more expensive the repair – it can be cheaper in more extreme cases to fit a new engine.

The newer common rail (or HDi) diesel engines are particularly vulnerable – if fuel contaminated by pump wear debris gets as far as the common rail system you may have to replace the low and high-pressure fuel pumps, injectors, fuel rail, line filters and the fuel tank too.

Err.. How exactly are the AA/dealer going to quantify the damage? The affected components are not serviceable, you can't strip them and measure tolerances So it either runs well, poorly or not at all.

noumenon said:

Many systems use a low-pressure electric pump in the tank or sender unit and this begins to work as soon as the ignition is switched on, circulating the contaminated fuel through the pump and rail – so it's important not to turn the ignition on.

Too late in this case.

noumenon said:

Petrol in Diesel
If the car's still under warranty you should check with the franchised dealer regarding the correct remedial action – some manufacturers advise that seals and filters should be renewed even if the engine has not been run.

And make a note in the service history that the car has been filled with petrol. Come the time of a failure and no warranty.

noumenon said:

Modern diesel with common rail or unit injectors – if you've added any petrol at all then the car shouldn't be started and the tank must be drained.

Again too late!

noumenon said:

Other diesel engines (not common rail or unit injectors)
More than 10% (5 litres in a 50 litre tank) petrol – Drain the tank and refill with diesel
Less than 10% petrol – Top up with diesel and run normally

So, you are saying is have someone drain the contaminated fuel, strip the entire fuel system and check it for damage in some way, then replace the damaged parts. Or, replace all the fuel system components as the MUST be damaged because the car has run. At own expense!

Or, if the car has been run then the damage is done. Dilute the fuel as much as possible and hope that all evidence of the contaminated fuel has gone if/when it breaks down. There is a good chance warranty picks up the bill.

I know what I would be doing!

If the OP can post back an update...

Steve

[noumenon]

That's what the AA suggests. Personally, I wouldn't drive it any further. I'd get the tank drained and refil it to the brim with the best diesel I could find. That's a small cost compared to anything else and may prevent further damage.

I guess the AA's argument is - pay for a thorough check now. Given the value of the car, and the potential cost of fixing it if there is a massive failure, it's worth considering.

[noneedtolift]

BMW service procedure for this is a change of ALL the fuelling components for preciesly the reasons statet by the AA. The charge an absolute fortune.

I did the same with my 335d but didn't start it - I had the fuel tank drained there and then and filled it up right to the top with diesel. Judging by the amount of diesel that went in, it must have had about 10 litres of diesel/petrol mixture left in it but i still drove the car for about 50 kms.

I was still worried sick so emtied the tank again the next day and it still smelled of petrol quite badly. The car ran fine after that (kept it for another 6 months).

Bugger is, it voids the warranty (at least in Germany). I'd give the car to an BMW- independant and let him empty the tank (a pain as it is a complex shape tank) clean out the high pressure pump, all lines and renew the filter just to be save.

Sorry for the bad news..

[roofer]

noumenon said:

roofer said:

80/20 won't hurt, get it down to 3/4 tank and top it off again.

Edited by roofer on Monday 8th September 23:36

You know better than the AA?

Yes, seen it done 7 times now, one on half a tank mix. Funny the AA now offer an expensive callout for just such an eventuality?

Dealers will replace the lot, because they are thieving bds.....Same as all dealers,

[darren no 7]

wife done the same and run the car till it stopped i cleaned out tank and lines but about 3000 miles later the engine blew(timming chain snapped no lubrecation to fuel pump), got payed out from insurers as putting in the petrol was a accident!

[VerySideways]

stevesingo said:

The key is to keep topping up the tank in order to dilute the mix a soon as possible.

[bennno]

noumenon said:

roofer said:

80/20 won't hurt, get it down to 3/4 tank and top it off again.

Edited by roofer on Monday 8th September 23:36

You know better than the AA?

I did it twice recently in different cars and never had a subsequent problem. As per advice below keep on topping up regularly with diesel. Bet you did it at a BP station?

For those that dont realise Diesel is mixed with Petrol in winter months to stop it solidifying. The issue with modern engines is that diesel is a lubricant and petrol a thinner so they will mix but you want to keep topping up the diesel daily and dont run the tank dry for a couple of weeks.

Besides if you go to the dealer all they will do is charge you a few hundred pounds and mark the issue on your warranty notes which will potentially void it anyway.

Bennno

[noumenon]

roofer said:

noumenon said:

roofer said:

80/20 won't hurt, get it down to 3/4 tank and top it off again.

Edited by roofer on Monday 8th September 23:36

You know better than the AA?

Yes, seen it done 7 times now, one on half a tank mix. Funny the AA now offer an expensive callout for just such an eventuality?

Dealers will replace the lot, because they are thieving bds.....Same as all dealers,

Really? With modern high pressure cars? I know you can do it with older cars but.....

Personally, if I had a modern oil burner, I'd want the tank drained at least. It's not going to cost much and will be peanuts compared to the potential downside of a failure.

We're not talking about a £500 pug 405 here, we're talking about a seriously expensive to fix modern, complex BMW.