Start the car runs fine, once all the gauges have done their checks on occasions i get a sputtering idle (bum da bum da bum da bum) voltage drops to about 10 or 12, shift to neutral is fine but drive reverse or park, can push through it and will clear up.
Have replaced the following
MAP Sensor
Idle Air Valve
Mass Airflow
Alternator
Injectors
Fuel Pump
Fuel Filter

Im at a loss and im tired, any ideas or suggestions greatly appreciated. Also about 170,000 miles on the thing