Section 7 (Engine Controls - System/Component Tests - 4.3L.)

• Model Identification
  • Notes
  • Terminology
• Introduction
• Computerized Engine Controls
  • Control Unit
    • Notes
    • Ground Circuits
    • Power Circuits
• Engine Sensors & Switches
  • A/C On Switch/System Test
  • Brake Switch
  • Engine Coolant Temperature (ECT) Sensor
  • Intake Air Temperature (IAT) Sensor
  • Knock Sensor
  • Manifold Absolute Pressure (Map) Sensor
  • Oxygen Sensor (O2S)
  • Oxygen Sensor Heating Element
  • Throttle Position (TP) Sensor
  • Transmission Range Switch
  • Vehicle Speed Sensor (Pm Generator)
• Relays, Solenoids, Motors & Modules
  • Relays
    • A/C Relays
    • Fuel Pump Relay
  • Solenoids
    • Notes
    • Electronic Air Control (EAC) Solenoid
    • EGR Control Solenoid
    • Idle Air Control (IAC) Valve
    • Torque Converter Clutch (TCC) Solenoid
• Fuel System
  • Fuel Delivery
    • Notes
    • Fuel Pressure Regulator (Port Fuel Injection)
    • Fuel Pressure Regulator (Central & Throttle Body Injection)
    • Fuel Pump Oil Pressure Switch (Back-Up Circuit)
    • Fuel Pump Relay
    • Fuel Pump Relay By-Pass Procedure
  • Fuel Control
    • Fuel Injector(s)
    • Oxygen Sensor (O2S)
    • C-2, Port Fuel Injector Balance Test
  • Idle Control System
    • Idle Air Control (IAC) Valve
• Ignition System
  • Notes
  • Timing Control Systems (C-4 & C-5)
    • C-4, Ignition Control Circuit
    • C-5, Knock Sensor Circuit (Models Using External Spark Controller Module)
    • C-5, Knock Sensor Circuit (Models Using Knock Sensor With Internal Spark Controller Module)
• Emission Systems & Sub-Systems
  • Exhaust Gas RECIRCULATION (C-7)
    • System Test (Vacuum-Controlled Valve)
    • EGR Control Solenoid
    • Negative Backpressure EGR Valve
    • Linear EGR Valve (Digital Valve)
  • Fuel Evaporation Control (C-3)
    • Vapor Canister Purge Valve ("P" Series & 4.3L CPI)
    • Fuel Tank Pressure Control Valve ("C", "G", "K" & "M" Series -High-Altitude)
    • Thermostatic Vacuum Switch
  • Positive Crankcase Ventilation
    • Required Service
    • Checking PCV Valve Function
  • Thermostatic Air Cleaner
    • Damper Door - Wax Pellet Check
• Miscellaneous ECM/Pcm/VCM Controls
  • Notes
  • Transmission (C-8)
    • Torque Converter Clutch (TCC) Solenoid
    • Converter Lock-Up Signal At Transmission
    • Converter Lock-Up Signal From ECM/PCM/VCM
    • Shift Light (Manual Transmission)
  • A/C Clutch (C-10) & Electric Cooling Fan (C-12)
  • A/C Clutch (C-10)
    • A/C Clutch Relay
  • Cooling Fan (C-12)
    • Notes
    • Cooling Fan Relay
    • Cooling Fan Motor
• Diagnostic Charts
  • Notes
  • Chart C-10, A/C Compressor Clutch Circuit Diagnosis - 4.3L (VIN W & Z) S" & "T" Series A/T & 4.3L (VIN W) "T" Series M/T
    • Notes
    • Diagnostic Aids
  • Chart C-10, A/C Compressor Clutch Circuit Diagnosis 4.3L (VIN Z) "S" & "T" Series M/T (1 Of 2)
    • Notes
    • Diagnostic Aids
  • Chart C-10, A/C Compressor Clutch Circuit Diagnosis 4.3L (VIN Z) "S" & "T" Series M/T (2 Of 2)
    • Notes
    • Diagnostic Aids
  • A/C Request Signal Circuit Diagnosis - 4.3L VIN W & Z ("C", "G", "K", "L", "M" & "P" Series)
  • Auxiliary Cooling Fan Circuit Diagnosis
• Component Locations
• Wiring Diagrams
  • Astro & Safari - VIN W
  • "C" & "K" Series - With A/T
  • "C" & "K" Series Pickup & Sierra - With M/T
  • "P" Series - With M/T
  • "P" Series - Commercial Van/MOTORHOME - With 4L80-E
  • "S" & "T" Blazer, Jimmy, Pickup & SONOMA - VIN W W/Pcm
  • "S" & "T" Blazer, Jimmy, Pickup & SONOMA - VIN W W/VCM
  • "S" & "T" Blazer, Jimmy, Pickup & SONOMA - VIN Z W/Pcm
  • "S" & "T" Blazer, Jimmy, Pickup & SONOMA - VIN Z W/VCM
  • Van - With 4L60-E
  • Van - With 4L80-E