'16 A7 fuel gauge issue

[MEgearhead]

The fuel gauge in my '16 A7 has decided to quit. I was getting low so I filled up, but it remains on E. It's like it is ignoring the sensors and just displays a calculated value without considering that I filled it up. Here's what I could find in advanced measuring values:

Address 17: Instruments (4G8 920 985 Q)

22:28:46
IDE00304 Fuel level 0 l
IDE03473-IDE00730 tank sensor-Fuel level sensor 1 including soiling resistance 55 Ohm
IDE03473-IDE00731 tank sensor-Fuel level sensor 2 including soiling resistance 93 Ohm
IDE03473-MAS03798 tank sensor-Raw value sensor 1 resistor 1 225
IDE03473-MAS03799 tank sensor-Raw value sensor 1 resistor 2 607
IDE03473-MAS03800 tank sensor-Raw value sensor 2 resistor 1 329
IDE03473-MAS03801 tank sensor-Raw value sensor 2 resistor 2 579
IDE03474-IDE00304 Calculated volume-Fuel level 0.0 l
IDE03474-IDE00306 Calculated volume-Fuel Level Sensor 1 52 Ohm
IDE03474-IDE00307 Calculated volume-Fuel Level Sensor 2 89 Ohm
IDE03474-IDE00312 Calculated volume-Fuel level from sensor 1 45.0 l
IDE03474-IDE00313 Calculated volume-Fuel level from sensor 2 28.8 l

Just wondering if anyone else has had this issue.

 

[MEgearhead]

Update

I decided to look at the tank calibration values. There appears to be 3 different calibration settings: complete, sensor 1, and sensor 2.

The current values for the sensors were very different. One was just above zero and the other something like -12 l. I changed the negative one to match the other one and immediately the gauge read full and the mileage to empty read 540 (previously 0 even with a completely full tank.)

Just for fun I changed the sensor calibration back to the -12 l it was before. Both the gauge and the MTE stayed the same (F and 540). After driving it 60 miles over a few days the gauge seems to be operating correctly.

Does anyone know the procedure for fuel tank level calibration?

In case anyone is interested, here are the same measuring values after changing the calibration setting. The car was not operated between these.

Address 17: Instruments (4G8 920 985 Q)

22:38:18
IDE00304 Fuel level 73 l
IDE03473-IDE00730 tank sensor-Fuel level sensor 1 including soiling resistance 55 Ohm
IDE03473-IDE00731 tank sensor-Fuel level sensor 2 including soiling resistance 93 Ohm
IDE03473-MAS03798 tank sensor-Raw value sensor 1 resistor 1 227
IDE03473-MAS03799 tank sensor-Raw value sensor 1 resistor 2 607
IDE03473-MAS03800 tank sensor-Raw value sensor 2 resistor 1 330
IDE03473-MAS03801 tank sensor-Raw value sensor 2 resistor 2 578
IDE03474-IDE00304 Calculated volume-Fuel level 73.0 l
IDE03474-IDE00306 Calculated volume-Fuel Level Sensor 1 53 Ohm
IDE03474-IDE00307 Calculated volume-Fuel Level Sensor 2 90 Ohm
IDE03474-IDE00312 Calculated volume-Fuel level from sensor 1 45.0 l
IDE03474-IDE00313 Calculated volume-Fuel level from sensor 2 28.3 l

 

[MEgearhead]

Update just in case anyone references this later. Its been a couple of months and two more tank fills. Gauge is working normally.

 

[MEgearhead]

Guess I spoke too soon. Today when I got in the gauge showed absolutely empty, 0 range, and all kinds of add fuel immediately warnings. This was with only 300 miles on a full tank. When I parked yesterday there was at least 1/4 of a tank. I knew there was fuel in it so I headed to work. After driving for about a mile the warnings went away, the gauge registered between 1/8 and 1/4, and the range came up to 100 miles. When I went to lunch and drove home from work there was varying behavior between those two conditions, and twice I got a fuel tank malfunction warning. I'll try to scan it this weekend.

 

[thebaz67]

Are you still under the extended warranty? I had the same issue and was, with some difficulty, get them to replace the fuel level sensor - which they attempted to claim wasn't a part of the fuel system, under the extended warranty.

 

[MEgearhead]

Yes I'm still under the extended warranty. However, the next day after the posting above the warnings went away and have not returned since. So, I'm just waiting to see how things go.

 

[thebaz67]

I ran into the same issue where it would work for weeks at a time and then suddenly stop.

 

[MEgearhead]

So, the fuel gauge went crazy again, but then miraculously fixed itself again. Approaching the end of the extended warranty, but don't know if I have the time, patience, and constitution to try to get the dealer to fix it.