Car smokes on start up only. If it sits for a month or more ther is a lot more smoke but only for a few min. Stock motor except for cold air intake and larger throttle body. Car has NOT been beaten or raced. It runs smooth except I have noticed when pulling off the highway onto onramp of interstate when you put your foot back on gas ther is a noticble hesitation. Take foot off gas and reapply and it's back to normal. There is no codes that have poped up and motor makes no odd noises at all. Starts up right away when key is turned. Fuel injector bad?