2005 Volkswagen Jetta Burning double the gas

If the engine were running too rich, the ECM would throw a trouble code. Have someone check for stored codes (even if the
check engine light is not on), then have the same person check the fuel trim values with the scan tool. Idle trim values and
cruising trim values. Anything in the range of +-5% can be considered normal.

Common issues are coolant temperature sensors, MAF sensors and thermostats that cause the engine to run cooler than
it should.

If the needle swings too much and when filling the tank, you can not put as much gas in as you think it needs. It could be
a fuel level sending unit issue (inside the gas tank).

If your Speedometer and odometer do not work (which can cause the fuel gauge needle to swing), replace the vehicle speed
sensor.

Thomas

Any progress?