My 99 Galant 4 cyl 2.4 makes a clicking sound when the engine is cold. when the car warms up the sound goes away. does anyone know what could be the problem? Is this serious?

Also, how critical is it for me to fix a silent shaft problem? Dealer gave me an outrageous price for the work on the timing belt.

 

Sounds to me like you have lifter tick. It is common with the 4G64. I use some CD-2 oil detergent and it works just fine.