VW Golf TDI Stalling & Power Loss at Idle: FPR Issue

Had a similar situation with my 2005 VW Passat TDI. The symptoms match exactly what happened, rough idle, significant power loss, and flashing check engine light. After changing the fuel filter, the engine started experiencing fuel pressure issues. The root cause wasnt the fuel pressure regulator, turned out the fuel pump was failing due to contaminated diesel. When the old filter was replaced, debris got pushed into the pump, accelerating its wear. The check engine light started flashing due to constant engine misfires caused by inconsistent fuel delivery. The repair required: Complete fuel pump replacement, System pressure test, Fuel line flush, New fuel filter installation, Computer system reset This was a serious repair that took several days to complete, as the entire fuel delivery system needed inspection and cleaning. The fuel efficiency improved dramatically after the fix, and the rough idle completely disappeared. Would strongly recommend getting a second opinion focused specifically on the fuel pump and having the fuel system properly diagnosed with pressure testing equipment. These symptoms rarely point to just the pressure regulator in TDI engines.

Thanks for sharing that experience with the Passat. My Golf had the same symptoms last year, its reassuring to hear the connection with the fuel pump rather than just the pressure regulator. Quick question, do you remember roughly how much the total repair cost? Also, have you noticed any pressure drop or other fuel system issues since getting it fixed? My mechanic quoted me 850€ for a similar repair scope but Im trying to gauge if thats reasonable. The check engine light hasnt returned on my car yet, but Im keeping a close eye on the fuel efficiency just in case the problem starts creeping back. Any long-term insights would be really helpful.

After getting the fuel pressure regulator replaced last spring and fixing the error entry for 45€, my TDI has been running perfectly. The fuel system now maintains consistent pressure with no issues or warning lights. That initial 850€ quote seems reasonable considering the full scope of potential repairs, but since my problem was simpler, I got lucky with just needing the regulator. The fuel efficiency has stayed stable and the engine runs smoothly at idle. I monitor the fuel rail pressure regularly through my diagnostic tool just to be safe, but havent seen any concerning pressure drops or check engine lights since the fix. If youre still experiencing symptoms, definitely have them check the entire fuel delivery system including the pump, as these issues can be interconnected. The key is getting an accurate diagnosis with proper pressure testing, it prevents replacing parts unnecessarily and saves money in the long run. My repair was straightforward once they properly identified the faulty regulator as the root cause.

I went ahead and took my Golf to a different mechanic for a second opinion, following the helpful advice here. Turns out you were spot on, it wasnt just the pressure regulator. The new shop did a complete fuel system diagnostic and found that the fuel pump was actually failing. The total repair came to 780€, which included: New fuel pump installation, Full system pressure test, Fuel line cleaning, Fresh fuel filter, Computer reset The engine runs perfectly now, no more stalling, full power restored, and the check engine light has stayed off. Fuel efficiency is notably better too. The repair took about 2 days, but it was worth the wait to have everything done properly. Really glad I got that second opinion instead of just replacing the regulator. Would have likely faced bigger issues down the road. The thorough diagnostic definitely saved me from future headaches and potentially more expensive repairs.