popping

When i drive my car in the morning while its still cold it makes a pop out of the exhaust every time i shift untill it warms up....what makes that and is it anything to worry about?

sounds like backfiring.. Could be caused by a number of things..
EGR, check your timing, check your plugs (gaps) wires, coil(s), and cap and rotor..
Could also be a vacumn leak.. can you hear any whistling under the hood?