Espace Hybrid Combustion Issues

The symptoms you describe – knocking combustion, reduced engine power, jerking acceleration, and smoke upon acceleration, coupled with a stored error – strongly suggest an issue within the combustion chamber. The higher octane fuel not resolving the problem indicates the issue is likely not fuel-related detonation. While a faulty knock sensor could contribute, the smoke points to something more substantial. Have you considered deposits accumulating within the combustion chamber? This can lead to pre-ignition and inefficient combustion. Could you provide more details regarding the error code that is stored?

Thanks for the quick response! I'll check the error code again to give you the exact details. But assuming it is deposits in the combustion chamber, what would be the best course of action? Is this something I could tackle myself, or would it be best left to a professional?

Given the complexity of modern hybrid engines and the potential for further damage, I would strongly advise against attempting a self-repair, especially concerning combustion chamber deposits. It's best to have a qualified mechanic diagnose the error code precisely and assess the extent of the deposit buildup. They possess the necessary tools and expertise to safely and effectively clean the combustion chamber. A misdiagnosis or improper cleaning could lead to more serious and costly engine damage. I highly suggest taking your Renault Espace to a trusted workshop as soon as possible.

Thanks for your advice. I took it to the shop, and you were spot on. Turns out there were significant deposits in the combustion chamber. They performed a cleaning service, and the knocking, smoke, and power loss are all gone. Cost me 425€, but it was worth it to have it running smoothly again.