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Test A - No Start: Notes

To prevent replacement of good components, be aware that the following non-EEC related areas may be at fault: fuel quantity and quality, ignition system damage, cracks, moisture, etc., engine mechanical conditions such as bad valves, timing belt, etc. Also included are starter and battery circuit problems.

  1. Try to start engine. If engine does not crank, check vehicle starting and charging systems. If engine cranks, but does not start or else stalls after starting, go to next step.
  2. Turn key off and wait 10 seconds. Set DVOM on 20-volt scale and disconnect Throttle Position Sensor (TPS). Turn key on, leaving engine off. Measure voltage at TPS harness connector between voltage reference (VREF) and signal return. If reading is less than 4.0 volts or more than 6.0 volts, go to TEST C - REFERENCE VOLTAGE  , step 1). If reading is between 4.0 and 6.0 volts, reconnect TPS and go to next step.
  3. Disconnect any spark plug wire and connect spark tester between plug wire and engine ground. Crank engine and check for spark. If spark exists, connect spark plug wire and go to step 13). If there is no spark, connect spark plug wire and go to next step.
  4. Remove high tension coil wire from distributor and install spark tester. Check for spark while cranking engine. If spark exists, connect coil wire and service or repair TFI ignition system. If there is no spark, connect coil wire and go to next step.
  5. Turn key off and wait 10 seconds. Install breakout box, leaving ECA disconnected. Set DVOM on 200-ohm scale and disconnect TFI. Measure resistance between test pin No. 16 and TFI harness connector ignition ground. If reading is more than 5 ohms, repair harness and repeat QUICK TEST  . If reading is less than 5 ohms, go to next step.
  6. With breakout box installed and box timing switch on "DISTRIBUTOR" position, connect TFI and ECA. Try to start vehicle. If vehicle starts, go to step 10). If vehicle does not start, go to next step.
  7. Move breakout box timing switch to "COMPUTED" position. Set DVOM on 20-volt scale and measure voltage between test pin No. 36 and chassis ground while cranking engine. If voltage is between 3.0 and 6.0 volts, EEC system is NOT at fault. TFI ignition system should be diagnosed. If voltage is less than 3.0 volts or more than 6.0 volts, go to next step.
  8. Turn key off and wait 10 seconds. With breakout box installed, disconnect ECA and TFI. Set DVOM on 200,000-ohm scale and measure resistance between test pin No. 36 and test pins No. 16, 20, 26, 40, and 60 for short to ground. Measure resistance between test pin No. 36 and test pins No. 37 and 57 for short to power. Measure resistance between test pins No. 36 and 56 for short to PIP. If any reading is less than 10,000 ohms, repair short in harness and repeat QUICK TEST  . If engine still does not start, go to next step. If all readings are 10,000 ohms or higher, go to next step.
  9. Turn key off and wait 10 seconds. With breakout box installed, connect ECA, but leave TFI disconnected. Set DVOM on 200 ohm scale. Measure resistance between test pin No. 36 and test pins No. 37 and 57 for short to power. Measure resistance between test pin No. 36 and test pins No. 40 and 60 for short to ground. If any reading is less than 5 ohms, replace ECA and repeat QUICK TEST  . If all readings are 5 ohms or higher, connect TFI and go to next step.
  10. With breakout box installed and DVOM on 20-volt scale, measure voltage between test pins No. 56 and 16, while cranking engine. If reading is between 3.0 and 6.0 volts, remove breakout box. Replace ECA and repeat QUICK TEST  . If reading is less than 3.0 volts or higher than 6.0 volts, go to next step.
  11. Install breakout box, turn key off and wait 10 seconds. Set DVOM on 200-ohm scale. Disconnect TFI and ECA. Measure resistance between test pin No. 56 and TFI connector PIP circuit. If reading is 5 ohms or more, repair open PIP circuit and repeat QUICK TEST  . If readings is less than 5 ohms, go to next step.
  12. With breakout box installed and ECA disconnected, turn key off. Disconnect TFI connector and set DVOM on 200,000-ohm scale. Measure resistance between test pin No. 56 and test pins No. 16, 20, 26, 40, and 60 for short to ground. Measure resistance between test pin No. 56 and test pins No. 37 and 57 for short to power. Measure resistance between test pin No. 56 and test pin No. 36 for short to Spark Output (SPOUT). If any reading is less than 10,000 ohms, repair PIP circuit and repeat QUICK TEST  . If all readings are higher than 10,000 ohms, diagnose TFI ignition system.
  13. Turn key off and wait 10 seconds. Disconnect ECA 60-pin connector and inspect for damaged pins, corrosion, or loose wires. Repair as necessary. Install breakout box and connect ECA. Make sure that box timing switch is in "COMPUTED" position. Set DVOM on 20-volt scale and measure voltage between test pin No. 36 and chassis ground while cranking engine. If reading is between 3.0 and 6.0 volts, go to next step. If reading is less than 3.0 volts or higher than 6.0 volts on all engines, go to step 10).
  14. Fuel Pump Check Connect pressure gauge to vehicle. Note initial pressure reading, then pressurize fuel system by turning key on for one second, turning key off, and then waiting 10 seconds. Repeat on, off, and wait sequence 5 times. Turn key off and wait 10 seconds. If pressure increased, go to TEST QQ - SYSTEM CHECK  , step 1) for EFI fuel injected engines. If pressure increased, go to TEST QQ - SYSTEM CHECK  , step 2) for CFI fuel injected engines. If pressure did not increase, go to next step.
  15. Inertia Switch Check Turn key off and install fuel pressure gauge. Locate fuel pump inertia switch and push button on switch to reset it to on. If switch will not reset to on, replace inertia switch and repeat step 14). If switch button was already on, go to TEST SS - IRCM  , step 11). Observe pressure gauge as system is pressurized as in step 14). If pressure reading increases, repeat QUICK TEST  . If pressure reading does not increase, go to TEST SS - IRCM  , step 11).
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