xantia revs

[timbo]

when changing gear my revs seem stick slightly before dropping, i have resently changed the exhaust back box
could this be why or is there something else that could be playing up?
Xantia 2.0 manual 94.

[philhoward]

Sticky ISCV (Idle speed control valve) is the first bet; pull it off (not literally) and it'll probably be gunged up. Carburettor cleaner and a toothbrush will work wonders on it.