Excessive Fuel Consumption
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 fuel injector circuits.
- Check Idle Air Control Valve-Auxiliary Air Control (IACV-AAC) valve circuit.
- Check ignition circuits.
- Ensure cooling system is reaching normal operating temperature.
- Check fuel pump circuit.
- Check Exhaust Gas Recirculation (EGR) system.
- Check fuel pressure regulator. See FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES article.
- Check EVAP system.
- Check PCV system.
- Check Camshaft Position (CMP) sensor circuit.
- Check Mass Airflow (MAF) sensor circuit.
- Check Engine Coolant Temperature (ECT) sensor.
- Check front Heated Oxygen Sensor (HO2S).
- Check Throttle Position (TP) sensor circuit.
- Check knock sensor circuit.
- Check Vehicle Speed Sensor (VSS) circuit.
- Check ECM power supply and ground circuits.
- Check A/C system.
- Check Park/Neutral Position (PNP) switch circuit.
- Check engine mechanical condition.