1992 Mustang LX stalls intermitently -HELP!

[amfw]

My 1992 mustang LX 2.3L Auto, recently began cutting out while driving. Usually, I can put it in neutral, and crank it right back up. It will stay running, and sometimes won't do it again for a day or two. It always starts right up when parked. A mechanic convinced me to replace the fuel pump and filter, after finding no ECC-IV codes to blame. HELP, it's still doing it! Please give me advice, as ECC and igntion switch are less than a year old. Thanks AMFW