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Problem -- Park the car overnight with fuel level showing ~1/4 tank remaining and the computer showing 100+ miles to go. The next morning, the fuel level gauge is buried at Empty, and the computer shows 0 miles to go. Go to a gas station and fill up, and you'll find that you were 5-7 gallons from empty.

Dealer Visit #1: No error codes found. Fuel tank level sending unit ordered.

Dealer Visit #2: Fuel tank level sending unit replaced.

Last night and one day later, I parked the car with fuel level showing 1/4 remaining, and the computer showing 95 miles to go. This morning, the fuel level gauge was buried at Empty, and the computer showed 0 miles to go. Went to a gas station, 18.5 gallons filled it up, indicating 5.2 gal remaining. Bummer.

Next suggestion?<ul><li><a href="https://forums.audiworld.com/a8/msgs/9154.phtml">Original fuel gauge problem thread</a></li></ul>

 

I have waited to take mine in for the same problem. I am not surprised they were not able to correct the problem. Let me know what they try next. I just ran mine down to about 100 miles left in range to see if it does it to me again.

John

 

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didn't generate much optimism that the dealer felt replacing the fuel sender would solve the problem. I'll be heading back to the dealer next week, but I'm afraid they may have to wait for a fix from Germany. I'll let you know what the dealer has to say.

BTW, during the same visit, the dealer also replaced my windshield. The ACCNA track event at Grattan two weeks ago resulted in a crack in the lower right in front of the passenger. Driving to the track on the Ohio Turnpike, a car kicked up a stone that smacked the glass less than one inch from the molding. The crack was growing about one inch per 50 miles, and I was seriously worried that the crack would grow out-of-control with chassis flexing at the track. I stopped at a Toledo auto glass repair shop at 4:15pm Friday afternoon to see if they could do anything and explained my problem to the manager of the shop. He drilled a hole at the end of the crack to stop the growth and filled it with UV curable resin. Two kudos here,

1. The charge from Harmon Autoglass was zero, and there was no further growth in the crack. They wouldn't accept payment because they couldn't guarantee that the crack wouldn't grow further.

2. Three Rivers Motor Car did an absolutely flawless job replacing the windshield, cost $597.

 

In speaking with my service dept. I was informed of some interesting facts (memory's little rusty so don't hold me to this): 1) There are actually three fuel measure sending units within the S8 tank due to the "saddle" design. All read at different levels and areas within the tank to provide the computer enough information determining fuel levels, mpg averages, miles remaining, etc. 2) Discussing the A6 fuel sending recall by AoA: I have learned the fuel quality in Europe is of a higher grade/purity than here in the US. As such, the impurities within our fuel has a tendency to attack and corrode the connectors on the fuel sensors within the tank. After time the result is false readings to the onboard computer. This is a problem with ALL European vehicles, not just Audi's. Speaking last week with a Mercedes owner within my building, he is experiencing the same issue with his '01 S500. My business partner drives a '99 M Roadster, fuel sensor has been replaced three times, same issue. Fortunately there's always fuel left in the tank. Audi, as I am informed, was the only European manufacturer who has issued a full recall (A6's in this case) within the US and replaced the fuel sensor with one that uses gold connectors.

My car has been in the shop for nearly to weeks now. A woman slammed into me doing about 20 mph while I was sitting at a stoplight. Her little Maxima "bounced" off my rear end, literally. For whatever distraction, she never had the opportunity to begin braking. Only damage to the S8 was the "bumper shocks" and exhaust tip (marred the finish). The bumper absorbed the entire impact. I was very impressed. Getting to the point, my service dept. received the car from the body shop on Friday and will begin work on the fuel gauge issue. More will follow....And, I've said it here before and will say it again, Cunningham Audi here in KC has one of the best Audi service dept.'s in the country. I suggest stopping by...

BTW - The reason the A6 was the only vehicle recalled was due the sensor giving a false reading which indicated there was still fuel remaining in the tank when actually there wasn't. In short, people ran out of gas. Audi will not issue a recall, such as the instance in the S8, since there is more fuel remaining in the tank than indicated.

Jim

 

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These are located inside the fuel tank? Seems like a strange place for something that could conceivably generate a spark.

Sorry to hear you were rear-ended, but glad that it wasn't more serious.

 

I think the problem here is that the computer monitors fuel consumption based on current conditions and unfortunately, in addition to the low fuel warning, it also manipulates the gas guage needle in order to urge you to get to the gas station.

I live in Toronto, so the mileage examples I will use here are kms - not miles. I drive about 60 kms one way to work so I love that big tank in the A8. I have only had my 1997 since December, but I began noticing this gas gauge issue almost immediately.

As the tank gets lower, I would leave the house and have 3/12'ths showing on the gauge and if I check the computer for distance to empty (DTE), it would show ~160 kms. So I would park at the office with the intention of filling at home that evening since I had at least 2/12'ths still showing on the gauge. However, I would go out after work, start the car and the Low Fuel warning would light, the computer DTE would show 60 kms and the guess gauge needle would be at 1/12 - half what it was when I parked the car.

The first couple of times this happened, I would head for the gas station before going home. Then I thought, I bet this is Audi once again going a little overboard so I tried to drive home one night. Sure enough, the longer I drove, the larger the DTE number became. In fact, once I get on the expressway and fuel consumption has stabilized, the DTE number can increase to the point that the low fuel warning light goes off. And guess what else - the fuel gauge needle also rises back up to the 2/12'ths position.

You can experiment yourself (with a couple of gallons of gas in the trunk), but this is what I have noticed. I now zero my trip meter each time I fill up since I know I can go 600 - 700 kms between fillups in the city and then I don't have to concern myself too much with what the computer thinks is going on.

Lauren

 

I believe that the "miles to empty" function works on the last 15 minutes of driving. Therefore, in winter, when the car is running rich just after start up, the miles to empty is a small number, after it warms up and you get on the highway it increases, which would explain your behavior.

However, I thought that the low fuel warning light was based on actual amount of gas in the tank and not dependent on fuel mileage at the time. This does not seem consistant with your explanation.

pw

 

But then, my driving is consistem and mostly highway.

 

I agree with what you say - but I think the DTE value is calculated based on the estimated fuel in the tank AND the current consumption rate. Also, if the car has been off for a period of time, does the computer store the previous 15 minutes of data somewhere or does it start with nothing? Based on my oberservations, I think the computer starts fresh with the ignition start.

I have left my office with the computer DTE saying I have a range of 60 kms at start up. Within 5 minutes or so, the DTE will increase to 80 kms or so. Once I hit the expressway, and the car is warmed up and rolling at speed (no, I'm not going to be specific ), the computer DTE can than increase to more than 100 kms at which point the low fuel warning light goes out. I can then drive the rest of the way home and still have 80 or more kms showing as the DTE. In other words, after driving 60 kms, the computer now says I can go further than when I started the car on the now diminished fuel supply - and the gas gauges is also reading higher!

What is truly bizarre is that they actually manipulate the fuel gauge needle to correspond to the DTE predictions.

Lauren

 

Me too - it is the quickest and easiest way to now what your remaining range is - no matter what the computer thinks!

I do this with all my vehicles.

Lauren