VW Fox Stalling: Fuel Sensor Warning Signs Explained

I had a similar issue with my 2003 VW Lupo diesel. As someone who regularly does basic maintenance but leaves complex repairs to professionals, this problem caught my attention because of the similar symptoms. The car dashboard was showing exactly what you describe, check engine light and inconsistent fuel gauge readings. The engine would stall at idle, which was particularly annoying at traffic lights. Initially, I thought it was a faulty sensor issue, specifically the fuel sensor. After taking it to the workshop, they discovered it was actually just a blown fuse connected to the fuel gauge circuit. The repair was straightforward and cost 52€ including diagnostic time. The mechanic explained that faulty fuses can cause these misleading symptoms, making it seem like a more serious fuel sensor problem. To better assist with your specific case, could you share: Have you checked the fuse box? What error code is your diagnostic tool showing? Does the fuel gauge show different readings when you fill up the tank? How long has the check engine light been on? These details would help determine if your issue is similar to what I experienced or if it might be something else in the fuel system.

Thanks for sharing your experience. My car had its latest service 3 months ago with nothing unusual found. The error code showing is P0180, and looking at the fuel gauge readings, they fluctuate wildly even when the tank is full. The check engine light has been on for about a week now. When I checked the fuse box yesterday, all fuses related to the fuel system appeared intact. The car electronics seem to behave differently each time I start the engine, sometimes the gauge works normally for a few minutes before going haywire again. Based on your repair story, this sounds more serious than just a blown fuse. Would be interested to know if anyone else has dealt with a confirmed faulty sensor showing these specific symptoms.

Thanks for providing those additional details. Your situation does sound different from my fuse issue, especially with that P0180 code and the erratic fuel gauge behavior. After seeing these symptoms in my VW Lupo, a faulty fuel level sensor is looking more likely in your case. When my fuel sensor eventually did fail about a year after the fuse incident, it showed similar symptoms to what you describe, fluctuating readings and car electronics acting up. The P0180 code specifically points to the fuel temperature sensor circuit, which often works in conjunction with the level sensor in the fuel tank. The repair in my case involved replacing the complete fuel sender unit. The total cost came to 320€, including parts and labor. The interesting part was that after the repair, not only did the gauge stabilize, but the idle problems completely disappeared since the car electronics were getting accurate fuel system readings again. Since you mention the gauge works normally for a few minutes after startup, this matches the classic behavior of a failing sensor rather than a wiring or fuse issue. A proper diagnosis would likely confirm this, but based on the identical symptoms in my car, preparing for a fuel sender unit replacement might be wise.

Thanks for the input. After reading about your experiences, I decided to have the car checked by a professional mechanic today. As suspected, the diagnosis confirmed a faulty fuel level sensor in the sender unit. The fluctuating fuel gauge readings and P0180 error code were clear indicators. The repair quote is 295€ for parts and labor, which seems reasonable compared to the 320€ mentioned. They can fix it tomorrow morning. The mechanic explained that replacing the entire fuel sender unit should resolve both the gauge readings and the idle issues, since the engine management system relies on accurate fuel sensor data. Will update this thread once the repair is completed in case anyone else runs into similar fuel sensor problems with their VW. The symptoms we discussed here, erratic fuel gauge behavior, stalling at idle, and the specific error code, could help others identify this issue earlier.