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Basic EEC Trouble Shooting

  1. Perform basic fuel system and ignition system checks, to ensure there is gas and spark.
  2. Remove air cleaner assembly and inspect all vacuum and pressure hoses for proper connection to fittings, or any broken, cracked or pinched conditions.
  3. Inspect EEC sub-system harness for proper connections to EGR solenoid valves. Red wire to both, Yellow wire to vacuum solenoid and Green wire to vent solenoid.
  4. Check for any loose or detached connectors or broken or detached wires. Ensure all terminals are completely seated.
  5. Repair items as required and replace air cleaner.
  6. Check battery charge, cable connections and main electrical wiring.
  7. Test resistance of all sensors and solenoids, using values given in EEC III COMPONENT RESISTANCE VALUES  chart. Be sure to disconnect component from circuit before checking resistance.
EEC III COMPONENT RESISTANCE VALUES

Component Wire Colors Resistance
Crank Position Sensor Gry-Dk Blu 100-640
Distributor Position Sensor Gry-Dk Blu 300-800
Coolant (ECT) Sensor Lt Grn/Yel-Blk/Wht 1100-8000
Air Charge Temp (ACT) Lt Grn/Ppl-Blk/Wht 1700-60.000
Throttle Position (TP) Sensor
Closed Throttle Org/Wht-Blk/Wht 3000-5000
Closed Throttle Dk Grn/Lt Grn-Blk/Wht 550-1100
Wide Open Throttle Dk Grn/Lt Grn-Blk/Wht 2100 or more
EGR Control Solenoid Red-Yel 30 or more
EGR Vent Solenoid Red-Dk Grn 30 or more
TK Solenoid Red-Red/Lt Grn 45 or more
TAB Solenoid Red/Wht/Red 45-90
TAD Solenoid Red-Lt Grn/Blk 45-90
Fuel Pump Relay Red-Tan/Lt Grn 40 or more
By-Pass Ballast Resistor N/A 3 or less
Fig 1: EEC-III System Testing - ECA Pin Voltages (KOEO Test)
G202106
NOTE: The pin number provided is for the positive lead of a hi- impedence digital voltmeter. The negative voltmeter connector can go to pin # 8 (Ckt. # 60) or a good body ground to complete the circuit test.