What is the reason for the intermittent malfunction of the Passat fuel gauge?
2 Answers
It is due to the damage of the fuel level sensor inside the fuel tank. Replacing the fuel level sensor inside the fuel tank can solve this problem. The following is relevant information: Passat fuel gauge pointer failure: The fuel level sensor detects the position (height) of fuel in the container by utilizing the change in capacitance between the sensor housing and the sensing electrode caused by the fuel entering the container, and converts this change into a current change. Application scenarios: Compact fuel level sensors for industrial use are suitable for measuring oil with a viscosity not too high under 5MPA and temperatures below 200℃, and can be equipped with various communication protocols; Special fuel level sensors for automobiles are suitable for measuring various fuel oils under normal temperature and pressure, with adjustable output damping time of 30-180s, and can support 485 communication.
I also encountered the issue of an erratic fuel gauge when driving my Passat, which is mostly related to the fuel level sensor. The sensor is installed inside the fuel tank and, after prolonged exposure to fuel, it can age or get clogged with debris, leading to inaccurate readings. Another common issue is loose wiring connections, especially those plugs in the engine bay—they can become unstable after prolonged vibration, causing the fuel gauge to work intermittently. A circuit fault in the dashboard itself might also be the culprit, so check the fuse box to see if any fuses are blown. I recommend visiting a repair shop to have it diagnosed with a scanner. Don’t delay, as driving without knowing how much fuel is left is quite dangerous—I once almost ran out of gas on the highway.
