VW Golf TDI Stalling Issue, Fuel Regulator Problems

Having worked on my own cars for several years, I faced nearly identical symptoms with my 2017 VW Passat TDI. The rough idling and check engine light issues you describe match my experience exactly. Initially, my local workshop also suspected the fuel regulator, but diagnostic testing revealed a failed high pressure fuel pump. These symptoms are quite common in TDI engines when the pump starts failing, poor fuel economy, rough idling, and significant power loss during acceleration. The repair cost me 1510€ total, including parts and labor. The workshop needed about 6 hours to complete the job, as they had to flush the entire fuel system to remove any metal particles that might have spread from the deteriorated pump. After the repair, all issues resolved completely, no more engine misfire, normal power delivery, and the check engine light cleared. Car sensors showed everything back to normal parameters. Could you share: Current mileage on your Golf, Any recent fuel system maintenance history, Whether you notice metal particles in the fuel filter, If any diagnostic codes were pulled from the ECU This information would help determine if your case matches what I experienced and provide more specific guidance.

I had the car serviced last month at 23784km. My local mechanic checked the fuel filter during that service and found no metal particles. They pulled the diagnostic codes which showed P0087 (Fuel Rail/System Pressure Too Low) and P0191 (Fuel Rail Pressure Sensor Circuit Range/Performance). The engine misfire symptoms started about 2 weeks after that service. I noticed the rough idling gets worse when the engine is warm, especially during stop-and-go traffic. Car maintenance records show no previous fuel system work has been done since purchase. Your experience with the high pressure fuel pump seems very similar to what I am experiencing. The quoted repair costs align with what my workshop estimated. I will have them do a thorough diagnostic check focusing on the fuel pump before proceeding with any repairs.

Thanks for providing those diagnostic codes and additional details. This definitely reinforces my initial suspicion of the high pressure fuel pump, especially with P0087 showing up. Just like your case, my fuel injection problems started becoming more noticeable in stop-and-go situations. The fuel pressure issues would cause significant drops in performance when the engine was under varying loads. After my repair, I implemented a few preventive car maintenance practices that have helped maintain proper fuel system health: Using only high-quality diesel fuel, Changing the fuel filter at every service interval, Having fuel pressure tested during routine maintenance The symptoms youre describing, combined with those specific trouble codes, create an almost identical pattern to what I experienced. Given that no metal particles were found in your fuel filter, catching this early could prevent more extensive fuel system damage. The repair costs tend to increase significantly if metal debris contaminates other components. Consider having them check the fuel pressure sensor as well, since P0191 could indicate issues there. However, in my case, this code was actually triggered by the failing pump causing irregular pressure readings.

The rough idling and check engine warnings match exactly what you both experienced. Based on the feedback and especially those diagnostic codes, I am now quite confident the high pressure fuel pump is the likely culprit causing my automotive repair needs. I appreciate the detailed explanation about potential fuel system complications if left unaddressed. Will definitely have my mechanic do the full diagnostic testing you suggested, focusing on both the pump and pressure sensor. The car maintenance tips about using quality fuel and more frequent filter changes make a lot of sense for preventing future issues. I have already scheduled the repair for next week. The workshop quoted 1450€ for parts and labor, which seems reasonable given your experience. Really hoping this resolves the fuel economy and performance problems I have been experiencing. Thanks for sharing your expertise. It helped confirm my mechanic's assessment and gave me confidence to proceed with the necessary repairs before the issue causes more extensive damage to the fuel system.