ECU data logger. ALDL diagnostic serial port  parameter names: 1995 PUB. list:   ( I merged the 8v and 16v values in to one table)   values are hot engine idling and not moving , 0 mph. Items in blue are 8 valve and 16 Valve differences. Items in Red are very criticle items for troubleshooting driveablity or MPG issues. FUNCTION UNITS TYP.VALUE   and RANGE ENGINE SPEED RPM 800 ±50  0-9999 DESIRED IDLE  R RPM ECM cont. varies   0-2000 ENG. COOL TEMP °C/F 176-194°F typ.   -40 to250°F 8V Intake Air Temp °C/F 149-167°F typ   same 16V MAS AIR FLOW  MAF. g/S 3.1g/S  THROTTLE POSITION volts .85 to .95Volts [idle] (0 to 5.1vdc  WOT) TROTTLE ANGLE ° 0° at idle   up to 90° max.  (wot=  80 typ) 8V  MAP Manifold Air Pressure kPa,V 39 kPa / 1.56v   0-125kPa range, 0-950 mmHG 8V BARO kPa,V 98 kPa / 4.00v    same range above, use only for altiude HO2S (OXY) mV 10-900 mV typ varies.        0-2500mV O2 ACTIVATION true/false active or not.  "Closed loop op's" S.T FUEL TRIM na 127 typ counts     0 to 255  ( 128 is center pt) L.T FUEL TRIM na 118 typ counts     0 to 255  (128 is center pt) SPARK ADVANCE ° 5°-15°   up to 60° INJ. PULSE WIDTH mSEC 1.1-1.6 mSEC   0 to 65mS IAC/ ISC AIR FLOW L/MIN 24-40 L/MIN   ,( 0 t0 250 max.) IAC/ ISC  ADJUST MONITOR % 0% typ and up   to 100% IDLE SWITCH (TPS) on/off  on 8v THROTTLE OPEN SOLENOID on/off off FUEL PUMP on/off on EGR GAS TEMP (CALIF) °C/°F 140 TO 145°F   (32 to 470°F ,max) EGR SOLENOID on/off off A/C SWITCH on/off off POWER STEERING SWITCH on/off off PARK/NEUTRAL POS P-n or R-DL P-n =Auto, R-DL manual MPH/KM/HR MPH/km/hr 0/0   -parked  (0 to 125mph max) FUEL EVAP PURGE % 0%  (100% max)  8v shows on or off. RICH LEAN STATUS rich/lean switches  will show lean if  HO2S is low all the time. (or opposite) SYSTEM VOLTAGE volts 14-14.5 volts (20v max)  0 to 18.75vdc range 16 VCHARGING EFFi % 10%   (100% max) 8V time from start sec 0-510 sec and rolls note: Fuel trim counts above are normal.  EG: 128 STFT is normal below is leaner , above 128 is too richer. same for LT fuel trim. note STFT is centered, as this is normal and the LT shows 10 counts lean , which is normal for intrinsic rich , non closed loop operations. this data chart represents what is displayed by the GM Tech1 scan tool. Note that a person can calculate MPG by using Inj. pulse width and MPH parameters.   It would be relative MPG such that you could find what speed and gear gave the highest amount. (not calibrated) refr: 6E3-A-14  and 6E2-A-10  FSM  1995 pub.