Hi guys, I've been chasing this problem for a while now, with no luck. The symptom is engine vibration on idle, when the engine gets warmer (when it's cold, you can't really feel it). Happens only on idle and the vibrations sort of go in waves (from less to more and back again) rather than being constant. There's no change of idle, the rpms seem to remain perfectly steady, but you can feel the vibrations through the seat. Thus far I've replaced the main engine mount (the one with the oil) and the two dogbone mounts (upper and lower) have been recently replaced as well. Replacing the main engine mount reduced the vibrations somewhat, but haven't eliminated them. I've also put in new sparks and new injectors. New injectors removed the rare occasional spitting/sputtering from the exhaust, so it doesn't do that anymore, but the vibrations on idle that come and go in waves have remained. The fuel filter was replaced as well, although the car has been driven exclusively on premium fuel since day one. It's now 8 years old, with 45k miles. I've borrowed a full set of coils from the newer Clio 200 that had no issues and tried them, also no to no avail. Recently, I've put the valve cleaner additive that my mechanic suggested, blasted the full tank with aggressive driving, no change. I've removed the intake duct and looked at the throttle valve, but it seems quite clean. Any ideas/suggestions?
