GMC C3500 HD (1991-2000) Wiring diagram engine performance 7.4l (vin n)s, m/t

7.4L ONLY A/C ON SIGNAL IN AIR CONDITION- ING SYSTEM BLK WIRE BLK/WHT WIRE BRN WIRE BRN/WHT WIRE COOLANT TEMP. SENSOR CRUISE CONTROL SYSTEM CRUISE IND REG GRD DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE DLC SERIAL DATA DLC THROTTLE POSITION SENSOR IN LO SIDE INJ A ECM-I MINI FUSE EGR VALVE SOLENOID (4.3L ONLY) (RIGHT SIDE OF ENGINE) EGR VALVE SOLENOID SHIFT LAMP CONTROL ELEC FUEL PUMP IN MAP SENSOR IN ENG-I MINI FUSE EVAP CANISTER PURGE CTRL EVAPORATIVE CANISTER PURGE SOLENOID (7.4L ONLY) (RIGHT SIDE OF ENGINE) FUEL PUMP RELAY CTRL GRY WIRE HOT IN RUN OR START IDLE AIR CONTROL UNIT (RIGHT REAR OF TBI UNIT) IDLE SPEED CONTROL IGNITION BYPASS IGNITION CONTROL (IC) VSS BUFFER SIGNAL VSS BUFFER SIGNAL KNOCK SENSOR IN PINTLE POSITION SIGNAL LT BLU/BLK WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE LT GRN/WHT WIRE MIL INDICATOR CTRL ORG/ WIRE OXYGEN SENSOR LO PNK WIRE POWERTRAIN CONTROL MODULE (UNDER RIGHT SIDE OF I/P) PPL PPL 1 2 3 4 PPL/WHT WIRE RED/BLK WIRE TAN WIRE TAN/BLK WIRE TAN/WHT WIRE THROTTLE BODY FUEL INJECTOR #1 (TOP OF THROTTLE BODY UNIT) THROTTLE BODY FUEL INJECTOR #2 (TOP OF THROTTLE BODY UNIT) UNDERHOOD FUSE/RELAY CENTER (LEFT REAR OF ENGINE COMPT) WHT DK GRN/ WIRE WHT WIRE WHT/BLK WIRE YEL WIRE

4.3L ONLY 423 3 121 PNK WIRE ACCY BLK WIRE BRN WIRE BRN/WHT WIRE BULB TEST DISTRIBUTOR (CENTER REAR OF ENGINE) DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE ENGINE COOLANT TEMPERATURE SENSOR (FRONT OF ENGINE) GAUGES FUSE 4 GRY WIRE HOT AT ALL TIMES HOT IN RUN, BULB TEST OR START I/P FUSE BLOCK (BEHIND LEFT SIDE OF I/P) IGNITION COIL (CENTER REAR OF ENGINE) IGNITION SWITCH INSTRUMENT CLUSTER KNOCK SENSOR (4.3L ONLY) (REAR OF ENGINE) KNOCK SENSOR (RIGHT SIDE OF ENGINE, BELOW EXHAUST MANIFOLD) LINEAR EGR VALVE (7.4L ONLY) (RIGHT SIDE TOP OF ENGINE) LOCK OFF LT GRN WIRE MANIFOLD ABSOLUTE PRESSURE SENSOR (RIGHT REAR TOP OF ENGINE) NCA WIRE ORG/ WIRE PNK WIRE PPL PPL 1 2 3 4 PPL/WHT WIRE RED/BLK WIRE RUN WIRE SERVICE ENGINE SOON INDICATOR TACHOMETER TEST LEAD TAN WIRE TAN/BLK WIRE THROTTLE POSITION SENSOR (RIGHT SIDE OF THROTTLE BODY) UPSHIFT LAMP WHT WIRE WHT/BLK WIRE YEL WIRE

4.3L ONLY BLK WIRE BLK/WHT WIRE BRN WIRE DATA LINK CONNECTOR (UNDER LEFT SIDE OF I/P) DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE ECM-B MINI FUSE FUEL PUMP AND SENDER FUEL PUMP OIL PRESSURE SWITCH (TOP REAR OF ENGINE NEAR DISTRIBUTOR) FUEL PUMP PRIME CONN- ECTOR FUEL PUMP RELAY (UNDERHOOD FUSE/RELAY CENTER) GRY WIRE HEATED OXYGEN SENSOR (IN EXHAUST Y-PIPE) HOT AT ALL TIMES IDLE SPEED CONTROL ACTUATOR SOLENOID (7.4L ONLY) (SIDE OF THROTTLE BODY UNIT) INSTRUMENT CLUSTER LT GRN/BLK WIRE OIL PRESS IN ORG/ WIRE PNK WIRE PPL PPL/WHT WIRE RED WIRE TACH IN TAN WIRE UNDERHOOD FUSE/RELAY CENTER (LEFT REAR OF ENGINE COMPT) VEHICLE SPEED SENSOR (LEFT REAR SIDE OF TRANSMISSION) VEHICLE SPEED SENSOR BUFFER (UNDER RIGHT END OF I/P) VSS IN WHT WIRE WHT/BLK WIRE