i have a clio phase 2 172 i have a knocking noise when accelerating hard in 1st gear also when reversing if i pull the clucth out fairly quickly and in 1st gear if i accelerate slowly up to about 3 thousand rpm and then take my foot off the accellerator pedal it jolts and theres a knocking sound its worse when it first gets started up it was doing it even in second gear this morning when it was cold im really not sure what the problem is would appreciate any ideas thanks luke