How many miles on engine? Manual or auto trans?Last time/mileage the timing belt was changed? Vacuum leaks , faulty mass air flow meter or air leak in intake hose(s) Poor quality fuel/running lean , ignition timing incorrect. Properly diagnose BEFORE spending on a bunch of guesses.
review when last tuned. it may be due.
rec. fuel system clean. ethanol treatment to 1 tank premium. ethanol blend in fuel causes build up in fuel system, combustion chambers, exhaust system and causes increased wear to spark plugs. may help rough idle and odd noise.
rec. oil stabilizer treatment on next oil change. recondition cylinders and seals. improve compression.
rec. take it in for diagnostic run to find any other issues u need to be aware of.