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Key On-Engine Running (KOER) Test

  1. Start engine and raise speed to 2500 RPM within 20 seconds after start. Hold RPM until 2 initial pulses appear. Continue holding speed until code pulses begin (10-40 seconds). Ignore any pulses that are more than 1 second in duration.
  2. Return engine to idle when codes begin. If code 11 is displayed, proceed to "Canister Purge Check". If any code(s) other than code 11 are displayed, perform test for code(s) indicated and repair problem(s) before proceeding to next test.
  3. If voltmeter does not pulse or pulses more than 2 times during first 7 seconds, perform Test 11 ("Tachometer Lead Test"). If voltmeter does not pulse, but shows steady high or low readings, perform Test 10 ("No Diagnostic Code; Functional Test Not Operating").
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