What OP is telling, is correct, if it is an IDE engine (direct injection). These injectors have a correction code, just a like a commenrail diesel. This needs to be coded via the CLIP, whitch can be done via Renault dealer. But i doubt that OP has an IDE eninge, i thing he has a good old 1.6 8V.
I would preforme a cilinder leak test, to see if the valve wont be leaking, this was a more commen fault, the reason was the vacumhose the MAP sensor, this was leaking, witch would cause a wrong mixture, witch cause the valve to burn out.
O btw, cilinder #2, is counted from the gearbox side, not from the timingbelt side. 😉 Gotta love the french 😛