My car is drunk...

[Zorb]

...or something like that.

I let a friend take it for a day and he out of habit put e85 fuel in it on the way back home to me because it is what he uses in his very tuned 335i. The car was barely over half a tank when he took it, and about 5/8 when he brought it back. He says he put in $20 worth, which as our local E85 prices of $2.59, leads to about 8 gallons.

Now, he did this at a gas station about 3 miles from my house, and claims it ran fine on the way home. I also found it to drive just fine, other than the fuel rates on the DIC being very bad. I was very careful with it and ran it down to about 3/8 tank of fuel and then topped it off with BP 93 gasoline.

Mileage numbers stayed bad over the next 100 miles or so, but it continued to run fine.

After parking it for about 6 hours, I started it to head home and it ran quite badly if pushed past about a quarter throttle and 2300 RPM. I topped it off again with BP 93 fuel (about 8 gallons) and the problem persists. I have since disconnected the fuel line and extended it into a gas can, jumpered the fuel pump relay, drained the tank to E on the gauge, and added 20 gallons of new BP 93 fuel. The problem remains. Hoping for a service engine light soon so that I can chase this further.

Anyone have any ideas?

I have never seen an accidental misfueling do this.

[lswing]

Yikes...I do know you need a lot more fuel being injected to run E85 as it burns up. Hopefully you didn't cook any rings from it running lean/hot. Maybe clogged fuel filter or injectors? Dunno, but I would have siphoned that E85 right out of my tank, seems scary to take a chance on the mixed fuel when your car isn't tuned for it.

[Zorb]

Even GM tells you to basically just find a back road and drive very conservatively, topping the car off with proper fuel as soon as possibly, for amounts less than a full tank. This goes for most other companies as well. The only companies that takes huge issue are the Asians.

Going to try the filter, it is easy to do.

remember that engine under full boost will subject to the rings to a lot more heat than it will running the wrong a fuel when driven like Grandma.

[hahnmgh63]

I would think since it wasn't that much it shouldn't have been enough to do damage unless your friend really hammered on it. Today's cars with their plastic fuel tanks don't really get much junk in their tanks, especially if you use reputable gas stations but it can't hurt to change it as it might be time. Also run a scan to see if there are any codes. Might try an ECU reset but I don't think that's the answer.

[Zorb]

hammered on it and 3 miles 30 mile an hour roads? Not likely. tried disconnecting battery. Also reflashed to stock for easier diagnosability. Ironically, it runs better on the Eurocharged tune then on the stock software.

[4everRS]

Were there any codes?

E85 won't do much if any damage. On my first rs6 I tried it when I needed a fill. Pumped 5 gallons in to check it out, ran like crap, but there were no long term effects.

[ben916]

Sounds like your "buddy" just bought you a new-to-you BCY motor... $10k mistake on him...

[lswing]

Sounds like your "buddy" just bought you a new-to-you BCY motor... $10k mistake on him...

But I read on the internet that E85 doesn't cause any damage...must be these cheaply made Cosworth blocks, doh!

[Zorb]

I talked to the Audi dealer today... Their RS certified tech said that there is nothing that should be damaged by either E85 or bad gas if not driven under heavy knocking. At worst, top off, drive it down to half a tank nicely, top it off, and repeat a couple more times before driving it hard.

It could stir water in the tank, which would basically go away after a tankfull, it could also stir debris due to varying density (heavier than gasoline) that could block the filter. They said it should actually be good for the injectors, rails, basically everything after the filter. He went as far as to say that some companies use it to clean fuel systems, basically dumping 3 or 4 gallons of E85 into an empty tank, drive it 25 miles carefully, and top off with normal fuel. Worst case should be a blocked prefilter in the tank.

Now on to my next problem... The threaded at the top of the fuel pump bracket is turning with the bolt, so I may have to cut and replace the bracket. Anyone have an idea on that one?

[hahnmgh63]

Injectors needing a cleaning is kind of a farce nowadays as long as you use a Top Tier gasoline. Your injector may wear over time but you will find they will almost always be very clean unless you get bad gas (stay away from discount stations). Plus many states already run up to 10% Ethanol in their gas which more than necessary to clean anything the Petroleum detergents don't get. Never listed to anybody that tells you to add E85 to clean your injectors.
P.S. I won't go into the Farce of even having Gasohol in this country. Cost taxpayers more, bad for vehicles, doesn't help emissions as claimed, etc...

[Zorb]

It is my understanding that all gasolines are supposed to, at minimum, have sufficient detergency to eliminate all deposits which would be left by burning that amount of fuel. I am personally more or less exclusive to BP. Shell is a second choice.

Either way, the point is that there is little likelihood of permanent harm.

Now,to get that stupid bracket apart! Any suggestions?

[lswing]

Hopefully it's just one of the fuel filters, or pre-filter as you stated. I would worry that your friend hammered on the car with that E85 in the tank thinking he was going to get a show, and it didn't break until in your hands, but let hope not!

[DHall1]

Ahhh the great farce!

We need a good rant now and then. Lol



Injectors needing a cleaning is kind of a farce nowadays as long as you use a Top Tier gasoline. Your injector may wear over time but you will find they will almost always be very clean unless you get bad gas (stay away from discount stations). Plus many states already run up to 10% Ethanol in their gas which more than necessary to clean anything the Petroleum detergents don't get. Never listed to anybody that tells you to add E85 to clean your injectors.
P.S. I won't go into the Farce of even having Gasohol in this country. Cost taxpayers more, bad for vehicles, doesn't help emissions as claimed, etc...

[Zorb]

I am a fan of periodic injector cleanings when I first get a car, since I do not trust people to use good quality fuel. A 6 pack of Techron, one bottle every other tank, as soon as I buy a car has treated be very well.

I got the fuel filter done, no difference. Did leakdown and compression tests, no issues, so that shoots the rings comment made above.

Spark plugs looked fine, though I have 8 more new just in case. I have both new BKR7EIX and stock PFR7Q with 5000 miles on them, though I do like the former better despite people insisting on the latter here. Seems to run more smoothly under power and makes a notable mileage difference.

[Zorb]

Would the car run with the second fuel pump not working? How would one forcibly start it and not the in-tank pump, for testing purposes?

[P1054]

You should be able to hook power directly to the motor, it's fairly easy to access. Right by the fuel filter in front of the rear right wheel.

[Zorb]

I know where it is... Just wondered if there was a better way. Either way, it was not running. With the car running. I took a hammer and hit the fuel pump with the rubber grip part. It started immediately.

Wondering if it was just on its way out and since Ethanol has lower lubricating potential, it chose that moment to freeze up... As I said, it did happen after the car was stopped for a few hours.