Conversation Between NmexMAX and packleader45

I have a 1996 Nissan Maxima. The check engine light came on so I checked at AutoZone and Checker neither have an adapter for that year. So, I have a new battery, new alternator, new plugs new coils, replaced the Camshaft sensor, did the fuel injector test,ie with engine running disconnect each coil, nothing. Only when I disconnect the battery then reconnect, then she purrs like a kitten, and takes off like her tail is on fire. engine: 3.0 dohc. thinking could be the MAS, or O2 sensor, after about 6 or 7 miles she starts smelling like gas and she runs rough while at stoplights when in drive, when I stop and put her in neutral, smooth as silk. Any thoughts?