Engine Has Poor Fuel Economy

Check for vacuum leaks (oil filler cap, oil dipstick, hose connections, PCV hose, PCV valve and EGR system):

• Check air filter.
• Check idle speed.
• Ensure proper spark exists from ignition system.
• Ensure ignition timing is correct.
• Check engine compression, valve clearance, valve timing and timing belt (if equipped).
• Check EGR system.
• Check dashpot or throttle opener (if equipped).
• Check fuel-cut system.
• Check fuel injectors.
• Check cold start injector system (if equipped).
• Check airflow meter or vacuum sensor and wiring.
• Check coolant temperature sensor and wiring.
• Check Throttle Position Sensor (TPS) and wiring.
• Check oxygen sensor and wiring.
• Check air temperature sensor and wiring.