Polo Diesel Power Loss & Hissing: Intake System Alert

Had similar symptoms with a 2013 VW Golf 2.0 TDI. The engine misfire and power loss were caused by a faulty intake manifold control flap. The airflow control system malfunction triggered the engine light and caused unstable performance. The repair involved replacing the complete intake manifold assembly since the control flaps were integrated. This was a serious issue requiring immediate attention as continued driving could have led to further engine damage and increased fuel consumption. The hissing noise typically indicates a vacuum leak in the air intake system. The mechanic also found worn gaskets around the manifold that needed replacement to restore proper sealed airflow. Total repair time was about 4-5 hours. While the car was driveable, running it with a defective intake system risks damaging other components. Getting it diagnosed and fixed promptly is important to prevent cascade failures in the engine management system. Regular cleaning of the intake system and checking vacuum lines can help prevent similar issues. Consider having the EGR valve checked too, as it often contributes to intake problems on these diesel engines.

Thanks for sharing your experience. I had a similar manifold flap failure on my 2014 Polo last winter, rough idle, reduced power and that annoying hissing you mentioned. The engine misfire symptoms matched exactly what you described. Just wondering, do you remember the total repair cost for fixing your intake system? Mine was fairly expensive but worth it since the issues completely disappeared. Have you had any other problems pop up since getting it sorted? The shop recommended I do preventive cleaning every 30000km to avoid future airflow control problems.

Glad to help. Since getting the switch intake manifold control fixed on my Golf, the engine performance returned to normal with no recurring issues. The total repair came to 465€, which seems in line with typical costs for this type of airflow control system work. The preventive cleaning recommendation your shop gave is spot on. I follow a similar maintenance schedule, which has helped maintain proper intake system function. The initial investment in fixing the flap control problem was definitely worth it to restore proper engine operation and prevent further complications. Regular maintenance has kept the intake system working smoothly, with no reduced power or performance issues in the two years since the repair. The hissing noise and rough running completely disappeared after the faulty control unit was replaced.

Thanks for the advice. I finally got the car checked out at my regular shop. The mechanic confirmed the intake manifold flap was stuck, causing the air intake problems and engine light warning. The total bill came to 520€ including parts and labor. They had to order a new manifold assembly since the flap control unit was not available separately. Took them about 4 hours to complete the job. The car runs perfectly now, no more hissing noise or power loss during acceleration. Fuel economy is back to normal too. They did a full system cleaning while everything was apart and showed me the buildup that had accumulated. Following their advice, I scheduled regular intake system maintenance every 30000km to prevent future issues. Bit expensive but cheaper than replacing the whole assembly again. Really glad I got it sorted before any serious engine damage occurred.