Volkswagen P044100 Incorrect Flow Rate in Fuel Tank Ventilation System?
2 Answers
It is due to a leak or blockage in the activated charcoal canister. Below is an introduction related to automotive fault codes: Meaning: Automotive fault codes are codes reflected by the vehicle's computer ECU after analyzing faults that occur in the car. Common fault codes are usually caused by sensor malfunctions or poor sensor performance. However, some mechanical faults cannot be read by the ECU. The car's dashboard will display some basic fault indications, but those are only a small part. The main diagnostics still require the use of an instrument—a decoder—to read the codes. There are many types of decoders, such as the X-43KT300, but their working principles and the faults they read are the same. Classification: Fault codes are divided into real codes, historical codes, and sporadic codes. Real codes are easy to detect, historical codes, as the name suggests, are previously unresolved fault codes left behind, while sporadic fault codes are not fixed.
Last time I was driving my Volkswagen, the dashboard displayed a P044100 fault code, indicating an incorrect flow in the fuel tank venting system, which was quite annoying. Common causes include a loose fuel cap or aging seals causing leaks, leading to improper pressure in the system; or a stuck control valve affecting exhaust flow; even small cracks in tubing can cause air leaks. I immediately checked the fuel cap, cleaned it, tightened it, and then started the car and drove for a few minutes—the light actually went off. If this doesn’t work, it could be an internal component failure, requiring a visit to the repair shop for a professional scan to pinpoint the issue and replace the necessary parts. Ignoring it won’t just be bothersome due to the warning light; over time, fuel consumption may increase, and it could cause issues during annual inspections. So, I recommend having the mechanic check the seals regularly during maintenance as a preventive measure. Also, be gentle when closing the fuel cap to avoid damage from collisions.
