Feedback System (Altima, Maxima VE30DE, NX, Sentra, Quest, 240SX & 300ZX)

Ensure ignition timing and idle speed are adjusted. Refer to ADJUSTMENTS article. Warm engine to operating temperature. Run engine unloaded at 2000 RPM for 2 minutes. Enter self-diagnostic Mode II. See TESTS W/CODES article. If Red LED on ECM (or CHECK ENGINE light) does not flash at least 5 times in a 10-second period, perform IDLE MIXTURE adjustment procedure in ADJUSTMENTS article.