VW Amarok Diesel Losing Power + Strange Hissing Sound

Had identical symptoms on a 2016 VW Touareg TDI at 95000km. The intake manifold flap actuator failed, causing poor airflow control through the intake system. Main signs matched yours, power loss, rough engine performance, increased fuel consumption and that distinctive hissing from the engine bay. The manifold flap stuck in one position, preventing proper air distribution across engine cylinders. This created uneven airflow, explaining the jerky acceleration. The check engine light triggered due to the intake system detecting irregular air pressure readings. The repair required replacing the entire intake manifold assembly since the actuator is integrated. Not a quick fix, the intake system needed complete removal to access all components. The job took a full day at the shop since several sensors and connections required careful handling during reassembly. This is a known weak point in these engines. Postponing the repair risks further engine performance issues and potential damage to other components due to improper air-fuel mixture. Best to address it promptly at a shop familiar with VW diesel engines. The symptoms are quite specific to manifold flap failure. If diagnosed correctly, fixing this should resolve all the issues you described.

Thanks for sharing your experience with the Touareg intake manifold issue. Really helped confirm my suspicions about my Amarok problem. Curious though, do you remember roughly what the total repair cost was for your manifold replacement? Also, has everything been running smoothly since the fix, or did you notice any other engine performance issues pop up? Just want to get a sense of the repair costs and whether this really solves the reduced power and engine misfire problems completely before I commit to a shop. My Amarok is still showing those exact same symptoms you described with the air intake system.

After getting it properly diagnosed and fixed, my Amarok runs perfectly now. The airflow control is back to normal and the engine performs like new. Total cost was 465€ for replacing the faulty intake manifold flap switch control unit. The repair completely resolved all the initial problems, no more reduced power issues, hissing sounds are gone, and fuel consumption returned to normal levels. The intake system is working as intended with proper manifold flap operation, which restored smooth acceleration and eliminated the rough running. It has been 6 months since the repair and no other engine performance issues have surfaced. The investment was worth it since proper airflow control is crucial for engine health and efficiency. When the manifold flap works correctly, the engine gets optimal air distribution across all cylinders. Based on the matching symptoms in your Amarok, getting this fixed should solve your issues too. Just make sure to use a shop that regularly works on VW diesels and understands intake manifold diagnostics.

Finally pulled the trigger and took my Amarok to the repair shop yesterday. After all the helpful advice here, I felt more confident knowing what to expect. The mechanic confirmed it was exactly the intake manifold flap issue causing the engine misfire and power problems. Total repair came to 490€, slightly more than expected but worth every cent. They replaced the entire intake manifold assembly and recalibrated the airflow control system. Shop had it done in about 6 hours. Drove it home and the difference is night and day. No more hissing sounds, power is fully restored, and the engine runs smooth as silk. Fuel consumption is already dropping back to normal levels. Really glad I got this fixed before it could cause more damage to the engine. Thanks again for sharing your experiences. Having real info about the symptoms and repair costs helped me avoid getting overcharged or misdiagnosed.