Audi A7 TDI Power Loss Linked to Intake Manifold Issues

I had almost identical issues with my 2011 A6 3.0 TDI. Having some experience with diesel engines, I recognized similar symptoms, reduced power, poor engine performance, and that distinctive hissing from the intake system. The engine light came on during highway driving, and the car went into limp mode. After diagnosis, it turned out the intake manifold control switch was completely defective, affecting the entire air intake system. The faulty switch was causing incorrect air-fuel mixture, leading to the power issues and increased fuel consumption. The repair took about 4 hours at the workshop. Total cost was 465 Euro, including parts and labor. Since the fix, engine performance returned to normal and fuel consumption improved significantly. Before suggesting specific solutions for your A7, could you share: Current mileage, Any recent maintenance history, Whether the engine light shows any specific error codes, If the symptoms are constant or only occur under certain conditions These details would help determine if your issue is identical to what I experienced. The intake manifold problems are somewhat common on these engines, but its best to confirm with proper diagnostics.

Last service was at 172885 KM including oil change and regular maintenance. The engine misfire symptoms get worse especially during cold starts. My scan tool shows P2015 error code which confirms the intake manifold runner control circuit malfunction. Getting progressively worse with more frequent reduced power episodes, particularly during acceleration. Mechanic availability is limited this week so trying to gather more info on the repair scope while I wait for an appointment.

Thanks for the additional details. Your P2015 code confirms exactly what I experienced with my A6, its definitely the intake manifold flap control issue. The cold start problems you mention match my experience too, and like yours, my symptoms got progressively worse over time. The repair scope on mine included replacing the complete flap control unit, not just the actuator. When the airflow control system fails this way, its better to replace the entire unit to prevent future issues. The reduced power and rough running cleared up immediately after the fix. Important to mention, while waiting for your appointment, try to avoid heavy acceleration as the faulty intake system can cause further engine stress. My mechanic also recommended cleaning the complete air intake system during the repair since these issues often lead to carbon buildup. The P2015 code combined with your symptoms leaves little doubt about the diagnosis. Make sure to mention the error code to your mechanic, it will save diagnostic time and costs. Based on my repair experience, you should expect similar costs around 450-500 Euro for the complete fix. Would definitely recommend getting it done soon, as continuing to drive with compromised airflow control can lead to additional engine issues and even higher fuel consumption than youre already experiencing.

Based on info provided, looks like its definitely the intake manifold flap issue matching the P2015 code. The rough running and reduced power problems getting worse during cold starts make perfect sense with this diagnosis. Will book the repair as soon as the workshop has availability next week. The 450-500 Euro estimate helps with planning, and its reassuring to know the fix should resolve both the engine performance issues and high fuel consumption. Good point about avoiding heavy acceleration until its fixed, will drive it gently to prevent additional engine stress. Planning to request the complete air intake system cleaning too since the car already has 172885 KM on it. Just hope the workshop can fit me in soon since the engine light and performance issues are really becoming a daily hassle. Will update once its repaired to confirm if swapping the manifold flap control unit solves everything as expected.