Engine Controls - Tests W/Codes - 4-CYL CARBURETED

• Introduction
• Ecu Location
• "Hard Failures"
• "Intermittent Failures"
• Check Engine Light
• Retrieving Trouble Codes
• Notes On Trouble Codes
• Clearing Trouble Codes
• Repair Procedure
• Summary
  • No Codes Present, DRIVEABILITY Complaint Still Present
• Trouble Code Charts - CARBURETED Models
• Diagnostic Hints - CARBURETED Models
• Diagnostic Circuit Check
• Ecu Terminal Identification
• Test 1 - Ecu (B+) Circuit
• Test 2 - Ecu Power Source
• Test 3 Or Code 12 - Ignition & Rpm Signal
• Code 21 - O2 Sensor Signal (22R)
• Test 4 Or Code 22 - Coolant Temperature Sensor Signal
• Test 5 Or Code 25, 26 - Lean Or Rich Air/Fuel Mixture
• Test 6 Or Code 31 - Vacuum Switch Signal
• Code 42 - Vehicle Speed Sensor Signal
• Test 7 Or Code 71 - EGR System Malfunction
• Test 8 Or Code 72 - Fuel-Cut Solenoid Signal
• Test 9 - Charging System Circuit
• Test 10 - "Check Engine" Light Circuit