Poor Fuel Mileage
- Check intake air temperature sensor.
- Check engine coolant temperature sensor.
- Check barometric pressure sensor (if applicable).
- Check manifold absolute pressure sensor (if applicable).
- Check ignition switch.
- Check throttle position sensor.
- Check camshaft position sensor.
- Check crankshaft position sensor.
- Check power steering oil pressure switch.
- Check A/C switch (if applicable).
- Check park/neutral position switch (A/T).
- Check heated oxygen sensor.
- Check volume airflow sensor.
- Check fuel pressure.
- Check for MFI system malfunction.
- Check for idle air control motor malfunction.
- Check for fuel injector malfunction.
- Check for power transistor malfunction.