Megane Cylinder Pressure Fluctuations

I had a similar issue with my Megane. It sounds a bit like a domino effect, where one small problem leads to consequential errors. Could be a number of things triggering it, from head gasket issues to timing belt slippage or even camshaft problems. Have you considered issues with the fuel injector or turbocharger?

Head gasket, camshaft, turbo... sounds expensive! You had the exact same symptoms, though? How did you narrow it down? I'm trying to avoid a parts cannon approach.

Indeed, the symptoms were remarkably similar. Considering the complexity and potential costs involved, especially concerning components like the head gasket or turbocharger, I'd suggest a comprehensive diagnostic check at a reputable workshop. It's best to verify these components before considering their replacement. It proved to be a good investment as it allowed me to address the root cause of the problem accurately and avoid unnecessary expenses. This will provide a precise diagnosis. In my case, it was a miscalibration of a sensor, and the workshop reset it. Good luck!

Thanks for the advice. Took it to the shop, and you were spot on – a sensor was sending garbage data, causing all the other problems. They reset the sensor, and everything's running smoothly now. Repair cost: 0€!