Common abbreviations used in Nissan 240sx Service Manuals.
OEM = Original Equipment Manufacturer (stock replacement parts)
MAS = Mass Airflow Sensor
MAF = Mass Air Flow sensor
FSM = Factory Service Manual
ECU = Engine Control Unit
LSD = Limited Slip Differential
VLSD = Viscous Limited-Slip Differential
SOHC = Single OverHead Cam (1989, 1990 models)
DOHC = Dual OverHead Cam (1991-1998 models)
S13 = 1989-1994 240SX
S14 = 1995-1998 240SX