Knock Sensor: Testing and Inspection

1983 Chevrolet EL Camino V6-229 3.8LSECTION Testing and Inspection

Chart C-4C - EST Performance Check:




Wiring Diagram for Chart C-4C - EST Performance Check:





CHART C-4C - EST PERFORMANCE CHECK

Test Description:

1. Grounding the "test" terminal causes the system to go to a fixed spark advance which should be different from that obtained with EST operating.

Engine is run at fast idle to get more spark advance. Usually the change is enough so it can be heard in RPM change. If so, it is not necessary to check timing.


2. The check in drive is made because some engines will not have EST operating in P/N.


3. Checks to see if fault is in MAP/VAC system.

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.