Car turns over but takes several times before it actually starts then sometimes while I'm driving it will lose power when I push on the gas and also stall while driving I've replaced fuel pump fuel filter fuel rail sensor solenoid canister and throttle body its a 2007 Ford freestyle any ideas not even the mechanic that replaced everything can figure it out

find a better mechanic, one who understands live data,mode 6 data, and how to analyze it. He's just guessing and wasting your money. could be tons of thing, but do check the maf sensor first