car dies
After i had my o2 sensor replace underneath, my car started to die out when i am driving. i replaced fuel pump and filter and air filter. mechanic had it on computer and cnt find anything wrong with car. they check ignition coil and switch and pcm relay and air intake hose and check for any ground problem, and they cant find out why car keeps dying while driving. it dies out 2-4 for times a day in a 16 mile drive. What could be wrong?