Have a metallic dunk from f/n/s wheel station when going over bumps or uneven roads. Checked lower mounts, wishbone mounts and can find nothing. Garages have no found anything either!!
check the anti rollbar drop links they may feel ok when you try & move them by hand but will knock badly over bumps if worn, best remove one end so its loose and then check the balljoints for play ,these are a common cause of knocking on citroens,had 4 & had to do every one ,i would replace both of them if one is worn ,easy enough job & they are only about 12 quid each from euro car parts
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