but first try cleaning the whole C/L system.
As for the idle troubles what have you tried?
How do I clean the C/L system?
Idle cures so far are......
New HT leads
New plugs
New dizzy cap
New rotor arm
New vac pipes
Cleaned out all breathers and checked for cracks
Cleaned throttle body
New air filter
Cleaned ISV with carb cleaner
New Blue sensor
Timing and idle set
Still no joy with any of the above. It will be fine sometimes then others a real sod. It will idle between 750-1600 a few times (4-8 times) then settle at around 850.