My 2001 Ford Expedition just had the battery and starter replaced, but now, the car dies while I'm driving it as battery light and check engine light come one, yet it restarts on the 1st try

when you assert "it dies" does it seem like it's starved of fuel...like the fuel pump stops working or is intermittent? or are you confident that the coil is not getting any power?

is your vehicle in "the salt belt", certainly if it had seen a couple of icy, salty pavement some may corrode the basic connections to the Block~...and the battery cable connections can get corroded too~

not in the "salt belt". i lived in the northeast, but have been in florida for over 5 years. as to your first question, i'm really not sure. the slower i'm driving, the more likely it happens if that makes sense.

rkstrpbos. not exactly sure where to start here...the vehicle simply drops out....so....as if the gas pedal was unconnected...or cuts out MORE when the lights are on...in other words the ignition coil does not have the power that it needs?~ fuel pumps either work...or the stop working...so we can rule out a Weak Fuel system...tho possibly a fuel regulator is faulty? check at your shroeder valve (on the fuel rail) to see if there is fuel pressure~ there should be pressure as long as the key is in the "on" position~ really unsure of what to test here...having fuel pressure when the key is ON is a start~