along with a constant faint audible metallic tap at idle speed) can also be a symptom of the VVC system on the whole being in "defect mode" which see's the pulley still able to do its own thing but the ECU knows no difference (Nomally due to a camshaft position sesnor, camshaft target or circuit wiring fault) so shuts off control.
This is one of the most common misdiagnosis's on the K4M's deployed in the Megane II/Scenic II since 2004 with VVC and if you don't check the system is/is not functioning correctly with CLIP you can find yourself spending out your hard earned cash and still having the original problem. The current N/A and Turbocharged F4R's that employ VVC are not as common (197/200 included) but there are a few starting to crop up now with this cam sensor issue so don't be quick to blame the dephaser without having it correctly diagnosed.
Mick