Poor Fuel Economy

Definition: Fuel economy, as measured by an actual road test, is noticeably lower than expected. Also, economy is noticeably lower than it was on this car at one time, as previously shown by an actual road test.

POSSIBLE CAUSE ACTION

Dirty air filter ^ Clean or replace.

Fuel Metering ^ Check air/fuel ratio, (Verify O2 Sensor Voltage).
^ Check fuel pressure.

Speedometer inaccurate ^ Check speedometer calibration.