I got 1990 300zx TT 5 speed. It jerks when you press on the gas pedal in the morning when it's cold. The problem goes away when engine is warm. Smoke also coming out of the car when I am stack in traffic in idle. Not all the time just once in the while. A cloud covers the car and then it goes away everything is normal.I don't know where to start from any help would be appreciated. thanks