Avantime Chip Tuning Power Loss

The symptoms you describe, reduced engine power coupled with a stored error code after chip tuning, do suggest a potential issue stemming from the modification. Who performed the chip tuning and did the issue arise immediately afterward, or some time later?

It was some third-party provider, not the official Renault tuner. The problem didn't start immediately, it took a few weeks. What do you think is going on with the car computer now?

Given the delayed onset and that a third-party provider performed the chip tuning, it's plausible the issue lies there. It is possible the tuning has caused an incompatibility, which will likely persist without professional intervention. I would recommend taking the vehicle to a trusted workshop for vehicle diagnostics and potential correction of the car computer's programming.

Thanks! I took it to a local mechanic, and you were right, it was the tuning. They adjusted some settings to make everything work correctly again. Cost me about 180€, but at least the car runs smoothly now!