Rough Idle

WARNING: This page does not describe the selected car, but rather 9 other vehicles, including the 2002 Nissan Xterra, 2002 Nissan Sentra, 2002 Nissan Quest, 2002 Nissan Pathfinder, and 2002 Nissan Maxima. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Unless otherwise indicated, see appropriate SYSTEM & COMPONENT TESTING article for testing procedures.

Check ignition timing, idle speed and throttle position sensor adjustment. See THROTTLE POSITION SWITCH, IGNITION TIMING & IDLE SPEED in ON-VEHICLE ADJUSTMENTS article.
Check battery and charging system. See appropriate GENERATORS & REGULATORS article in STARTING & CHARGING SYSTEMS.
Check Idle Air Control Valve-Auxiliary Air Control (IACV-AAC) valve circuit.
Check fuel injector circuits.
Check fuel pump circuit.
Check Idle Air Control Valve-Fast Idle Control Device (IACV-FICD) (where equipped).
Check ignition circuits.
Check PCV system.
Check EVAP system.
Check Exhaust Gas Recirculation (EGR) system.
Check ECM power supply and ground circuits.
Check Camshaft Position (CMP) sensor circuit.
Check Mass Airflow (MAF) sensor circuit.
Check front Heated Oxygen Sensor (HO2S) circuit.
Check Engine Coolant Temperature (ECT) sensor circuit.
Check Throttle Position (TP) sensor circuit.
Check power steering pressure switch circuit.
Check electrical load signal circuit.
Check Park/Neutral Position (PNP) switch circuit.
Check fuel delivery system.
Check air intake system.
Check engine mechanical condition.