My car has a rough idle after replaceing plugs and wires etc. It runs rough to around 2krpms then it clears up and is fine till redline. The only other thing I can think of is sometime it idles normally and then theres a sound that comes from the air cleaner housing that sounds like a kazoo or buzzing sort of sound then it starts idling rough again. Any ideas?

 

Shutter valve is bad. That is where the sound in the air cleaner is coming from.
Shutter valve bypasses the carb, allowing fresh air into the rear rotor during decceleration.

 

well put Rogue.

you might have a vacume leak also