Engine Running Test (4 and 6 Cylinder)
- Start engine and raise speed to 2500-3000 RPM within 20 seconds after start. Hold RPM until initial pulses appear (2 for 4 Cyl., 3 for 6 Cyl.). Continue holding speed until code pulses begin (10-40 seconds).NOTE: If more than 2 or 3 initial pulses occur, go to test 15 to check for an open circuit in the tachometer signal.
- Return engine to idle when codes begin. Codes will be repeated once. Record codes, then stop engine and reconnect canister purge hose. Refer to code chart to locate appropriate test.