My Chevy Blazer S10 stalls or nearly stalls when I start it up in the morning to drive to work. It starts okay, but when I put on the brakes at a stop light and accelerate when the light turns green, the car acts like it's going to die, and sometimes does. I have to give it gas very gently or it will die. I have had mechanics at the local Chevy dealer working on it for three days and they can't figure it out. Please help!