Poor Fuel Economy: Sensor/System
- Observe the 24X crank sensor and Camshaft Position (CMP) sensor signal present parameters on the scan tool. If both are not responding, check the sensor feed circuit. Both sensors use a common feed circuit.
- Check the air intake system and crankcase for air leaks. Check the air intake ducts for being collapsed, damaged areas, looseness, improper installation, or leaking, especially between the Mass Airflow (MAF) sensor and the throttle body.
- Check for proper operation of the speedometer. See appropriate ANALOG INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT.