KostaT

I have a '98 1.8T quattro with just under 2000 miles. The fuel guage will go to a certain point when the car first starts, then rise about 1/8 tank over the first 10-15 minutes of driving. Also it seems to drop a bit if I am doing stoplight-to-stoplight driving in town, then go back up on the highway. Does anybody else's do this? Just one of the things that I am wondering whether or not they are normal as I am getting used to the car. Great car so far (and Im looking forward to it getting better).<p>Cheers,<p>Kosta

Lenny

The fuel gauge on my '97 1.8TQM has fluctuated up and down as much as 1/8 tank ever since the car was new. Dealer says that's "normal." I judge when to add fuel mostly by the trip odometer.

EW

it's accurate, too<p>eric

george

My fuel guage does the same thing. It rises by about an 1/8 of a tank after I start driving. I've also noticed that my fuel guage is "nonlinear". After I've filled my fuel tank, I get about 220miles for the first half tank, and then I get only about 120 miles for the second half tank.

Kyle Bailey

Steady at least. I can't vouch for the accuracy. Seems like another one of those things where there are two extremes, and nothing in between (radio reception, remote range, interior motion sensor sensitivity, etc.)<p>Kyle<br>'97 2.8

Cameron

After seeing this post and checking on my car, which does the same thing, here is my conclusion.<p>There are two things driving what appear to the driver to be "innaccuracies" in the fuel reading.<p>The first is very similar to the speedometer offset. The speedometer on the A4 (like other cars, including the Viper, NSX, Boxster, M3, etc.) reads a higher speed at a higher rate of speed. So it may read zero when you are going zero miles an hour, but it is two miles an hour high at 30mph and five miles per hour high at 60mph. The petrol guage reading appears to distort the readings by giving a *slightly* "longer" second half to the tank. So you fill it up, it's past the 1/1 mark. You get to the 1/2 mark. It will be slightly longer, with the same computed tripcomp gas mileage before you run out of gas as compared to finishing the first half of the tank. Probably so stupid people don't run out of gas.<p>There is a second reason, though. There is only one sensor in the gas tank. It appears the ECU constantly averages and re-averages its last twenty readings (taking one reading each eighth mile of movement or so) so it doesn't get "fooled." Otherwise, you could turn on the car parked 20 degrees uphill (you can do this with pre-97 Accords) and have zero gasoline. This way, if you're parked uphil, going uphill, going downhill, in a turning tunnel of significant length, etc. you will not get a flawed gasoline reading. This re-averaging looks like it's done in the processor before the fuel management computer, since there is a tiny box there that probably contains an 8-bit microprocessor handling small deviations in the reading and re-averaging.<p>Cameron<br>

dannb

My fuel gauge will indicate about 1/8 high, then come down slowly over 10-15 miles. When making short trips, it may never indicate low - I ran out of gas with 1/4 tank indicated when the car was a couple of weeks old. The service manager said it was a resistor in the instrument head that needed adjustment, but the guy who looked at it said it was a known problem with the A-6, but hadn't heard of it with the A-4 until he looked at mine. He didn't have a clue as to the cause.

Gus

Well when I park my A4 quattro uphill with less than 1/2 of a tank full, the gauge shows a lower reading and does not correct itself until the next fill up (stays like that even when turning back on the car the next day). Some folks explained this phenomon by mentioning the U - shape of the gas tank in quattros argument.<br>

Cameron

nt<br>