Amarok Fuel System Woes: Stalling and Power Loss Fix

Having experienced a similar issue with my VW Tiguan 2017, I can relate to your fuel delivery problems. The symptoms you describe, rough idle, stalling, and reduced power, along with the check engine light match what I encountered. In my case, after changing the fuel filter, the pressure sensor readings were inconsistent, causing a pressure drop in the fuel system. The workshop connected a diagnostic tool which confirmed irregular fuel pressure readings. The fix was actually simpler than expected. The mechanic found that the fuel filter installation needed proper bleeding of the system. After completing the proper bleeding procedure and resetting the check engine light, all issues were resolved. Total cost was 45€ for diagnostics and repair. Before suggesting more specific solutions, could you share: Have you recently had any fuel system maintenance? Are there any specific error codes from the check engine light? Does the rough idle happen more during cold starts or when the engine is warm? What fuel grade are you using? This information would help determine if your issue matches what I experienced or if it might be something different with your fuel regulator or other components.

Latest service was done at 35000km. The fuel rail pressure sensor readings from my scan tool show inconsistent values, fluctuating between 30-45 PSI when it should hold steady around 55 PSI. The check engine light codes point to low pressure in the fuel system. I noticed the rough idle gets worse after the engine warms up, typically about 10 minutes into driving. The stalling has happened three times now, always at low speeds. I do use the recommended premium fuel grade and changed the fuel filter about 8000km ago. My main concern is the pressure drop happening more frequently now. Could this indicate a failing fuel pump rather than just the regulator?

Based on those fluctuating pressure readings and the timing of your symptoms, this sounds more serious than my initial fuel filter bleeding issue. The pressure drop pattern in your fuel system, especially after warm-up, strongly suggests a failing fuel pump rather than just a regulator problem. In my case with the Tiguan, I initially thought it was just the fuel pressure regulator too, but when the check engine light kept returning and the rough idle persisted, further testing revealed similar pressure fluctuations. The fuel pump was failing intermittently, causing pressure to drop below the minimum threshold needed for proper engine operation. The replacement fuel pump solved all issues, stable pressure readings returned to normal 55 PSI, rough idle disappeared, and no more stalling. Total repair cost was around 600€ including parts and labor. The timing of your symptoms, worsening after warm-up, matches exactly what I experienced. The pressure drop becoming more frequent is a classic sign of a deteriorating fuel pump, not just a regulator issue. My suggestion would be to have the fuel pump tested thoroughly. The inconsistent pressure readings from your scan tool already provide strong evidence pointing in that direction.

I appreciate all the detailed feedback. The focus on the fuel pump degradation makes a lot of sense given the symptoms. The pressure drop pattern matches what you described with your vehicle, and the timing of issues worsening after warm-up seems to be a common thread. I will have the fuel pump tested before jumping to replace the fuel regulator. The scan tool pressure readings showing 30-45 PSI versus the needed 55 PSI definitely support this approach. Good to know a proper diagnosis caught the real issue in your case rather than just changing parts. The check engine light codes and rough idle behavior line up with what you experienced. Looks like I should budget around 600€ for the potential fuel pump replacement based on your repair costs. Much better to address the root cause than waste money replacing the wrong parts. Going to schedule testing of the fuel rail pressure and pump operation this week. Will update once I know more about whether the fuel pump is indeed causing these fuel delivery problems. Thanks for helping narrow down the likely culprit.