Kind of expensive to replace if Im not sure if its the problem. I guess the question is can heat cause the afm with problems to mess up, then after it sucks enough cold air, begin to function normal? Thinking about putting a fuel gauge on to see what the fuel is doing when it starts acting up. Does the afm on the toyotas tell the fuel pump how much fuel to send? if it does then a bad fuel pressure could be both the fuel pump or the afm telling the fuel pump the wrong thing? It does this problem every time like clockwork. Did it last summer for a couple months, then stopped and didnt start up till first of Jan. and has done it ever since.