90 Nissan Sentra 5 speed, cold or warm weather, my car sputters and losses power. I have to rev up engine till it starts running smooth. I put in new plugs, new wires, air filter and gas filter. This happens after car sits a few hours almost every day. I see alot of smoke when I try to start, but then it stops after engine is running smooth. Runs fine while driving. Any ideas, thx!