Megane Hybrid Turbo Issues

From your description, it seems likely that you are experiencing a boost pressure actuator fault. The combination of reduced power, unusual noises, and increased fuel consumption is indicative of such an issue. Without proper diagnostic tools, it's difficult to pinpoint the exact cause. However, given the symptoms, it’s plausible that the boost control system is malfunctioning. Have you noticed any unusual readings or error codes?

Thanks for your reply! It's reassuring to know I'm not completely off base. Error codes - yes, I have seen some codes relating to boost pressure. One explicitly mentioned the actuator. What I'm trying to figure out is whether it's likely to be a simple fix like a loose connection, or if the whole actuator is actually kaput? Is there anything I can check myself before I have to bite the bullet and take it to a mechanic?

While a loose connection is always a possibility, the error codes and symptoms you've described suggest a more significant problem with the actuator itself, or potentially related components within the turbo system. Given the complexities of modern hybrid engines and turbo systems, I would advise against extensive DIY repairs without specialized knowledge and equipment. A professional diagnostic assessment is necessary to confirm the fault and determine the best course of action. Considering the potential for further damage, it would be prudent to seek assistance at a reputable workshop.

Ok, I understand. Thanks a lot for your help! I took it to a trusted mechanic. The boost pressure actuator had to be replaced, luckily the electrical bypass valve was easy to fix. It cost me around 250€, but now everything is working fine!