I have a Lexus ES 300, runs fine for last couple of months I am having problem when I stop after driving some time at stop lights it starts jerking and engine makes more noise, after light turns green when I push gas it runs fine while driving, this is not always, after I park for couple of hours then start the car and drive it goes smooth. The mechanic said it is problem with Air flow meter and Mass Air flow sensor, is that true if I change the sensor will that fix the problem? Please help

You need to checked it up completely and follow the instructions of your trusted mechanic. Otherwise take it to the dealer for suggestion.

msg219 has rightly suggest that take your car to a mechanic I am sure he will fix this problem . Every thing will be ok then , Enjoy riding your Lexus ES 300 .