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Discussion Starter #1
The alcohol content of today's gasolines is causing severe problems in these direct injection engines. A recent tech article in 'The Roundel' recommended adding BMW Fuel System Cleaner to your gas every 3,000 miles. I discussed this with Mike O'Neill at Northeast Motorsports & he confirmed they are seeing many injection problems in these cars with as little as 25,000 miles. He recommends using 'Techron' as an alternative to the BMW Fuel System Cleaner.
 

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The alcohol content of today's gasolines is causing severe problems in these direct injection engines. A recent tech article in 'The Roundel' recommended adding BMW Fuel System Cleaner to your gas every 3,000 miles. I discussed this with Mike O'Neill at Northeast Motorsports & he confirmed they are seeing many injection problems in these cars with as little as 25,000 miles. He recommends using 'Techron' as an alternative to the BMW Fuel System Cleaner.
Good to know... what are the commonplace symptoms?

I've always associated Techron with Chevron--I'm assuming you're saying it can be bought as a separate additive?

I also assume ethanol-free gas is exempt from this problem?
 

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Discussion Starter #3
Good to know... what are the commonplace symptoms?

I've always associated Techron with Chevron--I'm assuming you're saying it can be bought as a separate additive?

I also assume ethanol-free gas is exempt from this problem?

The cars won't run properly and the injectors have to be replaced. I used to buy Techron for my E39 M5-S3 at Costco. Presumably ethanol-free gas won't cause a problem. It seems that even Tier 1 gasolines, i.e. Shell, contain up to 10% ethanol here in the U.S.

--Ray
 

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In some cities the U.S. EPA requires ethanol to be added to fuel. In Atlanta, GA where I live this is the case. It may be a seasonal thing with ethanol required in the Summer when smog is bad.
 

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All the direct injection engines are having issue, mostly carbon build up. I spoke to my Audi mechanic and he explained it clearly. When the fuel used to be sprayed into the intake runners before the valves the gasoline would act as a cleaner. Now that the fuel is being sprayed directly into the cylinder there is nothing cleaning the valves, injectors etc..... This is what the primary issue. The BMW issue may be different but running cleaners can help. Ive been running seafoam before every oil change to help prevent as much build up as possible. I spray it into the TB. pour some into the fuel tank and a small amount directly into the engine. I only run it in the oil for about 15 miles, the distance from my house to the shop.
 

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On the Audi DI problem front, there is a solution. Better PCV system. The one in the M5 is pretty ridiculous. Or the Lexus solution which is having both direct and port injector keeping the backside of the valves clean.
 

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I recently bought a x5m from Canada and from the records that I received from the BMW dealer there were never any issues with the injectors. I've put about 10kmi. on the car since then here in the USA and it seems that my injectors are gone. I'm trying to contact BMWNA to see if they'll do anything to remedy the problem (i.e. replace the injectors). There is even a service bulleting b001314 that covers the N63 engines but not the S63, and part of the bulletin are the injectors.
From reading all the forums thus far it seems that only vehicles in the US are having these issues which leads me to believe that it has something to do with the added ethanol in the gasoline here. I wish they would stop requiring the ethanol to be added to the gasoline, then maybe we could avoid some of these repairs.
 
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