VW Crafter Turbo Issues Causing Multiple Engine Symptoms

I experienced nearly identical symptoms with my 2015 VW Transporter TDI. The whistling noise and engine light were classic signs of a failing turbocharger system. After diagnosis, the issue traced back to a damaged wire harness connecting the boost pressure sensor to the intake manifold. The turbo boost signals were not reaching the engine control unit properly, causing the erratic performance. The engine light kept triggering because the pressure sensor was sending faulty readings. In these cases, its not always the sensor itself thats faulty, often its the wiring or connector that deteriorates. The fix required replacing the entire wiring harness section and recalibrating the turbocharger pressure settings. This was a serious repair that needed specialized diagnostic equipment. While not as costly as replacing a full turbocharger, it still required careful work to ensure all connections were properly sealed and calibrated. Given your symptoms, especially the whistling, poor performance, and high fuel consumption, I strongly suspect your boost pressure sensor circuit has similar issues. The jerking and stalling happen because the engine cant properly regulate turbo boost pressure. A qualified VW diesel specialist should start by testing the sensor connections and wiring before replacing any components. The complete diagnosis will reveal if theres additional turbocharger damage that needs addressing.

Thanks for sharing your experience. The symptoms on my VW Crafter match what you described exactly. The check engine light and boost sensor issues were really concerning. Did you need to replace any other parts in the air intake system during the repair? The whistling noise totally went away after fixing the wiring? Would really appreciate knowing what the total repair cost was for you. Want to have a rough idea before heading to the shop, and wondering if any other problems showed up since getting it fixed.

Had the repair done last week and can confirm it was the boost pressure sensor wiring causing all those issues. The mechanic found a damaged connection that was making the sensor send incorrect readings to the engine control unit. Once they fixed the cable connection, the check engine light stopped coming on and the whistling noise disappeared completely. The total cost was 95€ for the wiring repair, which was much cheaper than initially expected. No other parts in the air intake system needed replacement, the turbo and other components were actually in good condition. The engine is now running smoothly with normal fuel consumption, and the turbo boost is working as it should. Since the repair, everything has been perfect, no more jerking or stalling issues. The pressure sensor is now getting clean signals to the ECU, which means proper boost control. Would definitely recommend getting it checked soon, as these issues can lead to bigger problems if left unaddressed.

Just got back from the mechanic and wanted to share my experience. The boost leak turned out to be exactly what was described, a damaged wire harness by the pressure sensor. The mechanic showed me where the wiring had worn through, causing all those crazy symptoms. Total bill came to 120€ for parts and labor. They tested the whole turbo system while they were at it and found everything else working fine. Really relieved it wasnt something more serious. The repair took about 2 hours and the difference is incredible. No more check engine light, the whistling is completely gone, and the engine pulls strong again. Fuel consumption is back to normal too. Big thanks to everyone who helped point me in the right direction. Saved me from getting scammed into unnecessary repairs by showing me what to look for.