BOSCH LH-JETRONIC - Engine Control System

• Description
• Operation
  • Computer Controlled Ignition
  • Constant Idle Speed System
    • Electronic Control Unit
    • Air Control Valve
    • Throttle Switch
    • Coolant Temperature Sensor
    • A/C Switch
• Trouble Shooting
  • Engine Does Not Start
  • Engine Hard To Start (Cold & Warm)
  • Poor Or No Idle
  • Excessive Fuel Consumption
  • Poor Performance (Low Top Speed)
  • Erratic Idle
  • Idle Speed Too High
  • Idle Speed Too Low (Engine Cold)
  • Jerking, Poor Acceleration
• Diagnosis & Testing
  • Notes
  • Test No. 1 - Engine Starts But Will Not Run Properly
  • Test No. 2 - Testing System When Engine Will Not Start
  • Electronic Control Unit For The Constant Idle Speed System
  • Throttle Switch
  • A/C Switch
  • Coolant Temperature Sensor
  • Air Control Valve
  • Air Mass Meter
    • Check Air Mass Meter Current Supply And Ground
    • Air Mass Meter Resistance Check
    • Air Mass Meter Voltage Check
    • Check Air Mass Meter Measuring Wire Dirt Burn-Off
• Adjustments
  • Throttle Switch