Diesel Data: Automotive Repair

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 Injected Check air/fuel ratio,
Refer to Computers and Control Systems,
Check fuel pressure,
(check vacuum line and return hose)

Speedometer inaccurate Check speedometer calibration

Fuel leak Inspect fuel lines, tank
and fittings