GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 1998 🢒 GMC C-Series Medium Duty Truck B7 🢒 Brakes 🢒 Air Antilock Brake System 🢒 Engine Controls Component Views
Figure 1:

Engine Harness (LP4/L21), Upper Right Front View
Object Number: 235950 Size: LF
(1)Throttle Body Fuel Injector 1
(2)Throttle Body Fuel Injector 2
(3)Engine Speed Governor Motor
(3)Engine Speed Governor Module
(4)Engine Coolant Temperature (ECT) Gauge Sensor
(5)Engine Speed Governor Module
(6)Knock Sensor (KS) Module
(6)Knock Sensor (KS) Module
(7)Exhaust Gas Recirculation (EGR) Electronic Vacuum Regulator Solenoid Valve
(8)Throttle Position (TP) Sensor
(9)Idle Air Control (IAC) Valve
(10)Manifold Absolute Pressure (MAP)
Figure 2:

Engine Harness Components (LP4/L21), Upper Left Rear
Object Number: 216233 Size: LF
(1)Distributor Ignition (DI) Control Module C2 (2 cavities)
(2)Distributor Ignition (DI) Control Module C1 (4 cavities)
(3)Distributor
(4)Oxygen (O2) Sensor
(5)Engine Oil Pressure Gauge Sensor and Fuel Pump Switch
(6)Ignition Coil C2 (2 cavities)
(7)Ignition Coil C1 (2 cavities)
Figure 3:

Knock Sensor
Object Number: 311469 Size: SH
(1)Knock Sensor
(2)Knock Sensor Electrical Connector
Figure 4:

EVAP Canister
Object Number: 337479 Size: SH
(1)Right Side Frame Rail
(2)EVAP Canister