Car continues to over heat on 1998 Acura SLX

My 98 Acura SLX is still over heating. It has been in the shop for the past two weeks. When i start my car up and jus let it sit it is fine and does not overheat. But when I start driving it overheats and the cooling in the cooling tank bubbles and boils over. I've had the water pump, radiator, timing belt, and the thermostat replaced. I asked about the head gaskets but the mechanic said that they were fine. He also flushed all the fluids out. Does anyone know what else it could be? Someone told me to ask about the idle intake valve. Could that also need to be replaced?

Asked by for the 1998 Acura SLX
That sounds a very much like a head gasket or cracked head type of problem. You might have the mechanic check again, head gasket/cracked heads are often pretty hard to spot in testing. Many times it takes multiple test at different temperatures. Another indication is to apply pressure to the cooling system. Allow the vehicle to sit for a few hours with pressure applied. A misfire on startup adds more support to a head/gasket problem.

Good luck