Poor Fuel Economy

Fuel economy is noticeably lower than expected. Customer should drive vehicle and note miles per gallon decrease.

POSSIBLE CAUSE ACTION

EGR malfunction, Check the EGR system under
Flange gasket leaking, TESTING PROCEDURES.
solenoid and thermo valves
malfunctioning



Ignition timing Check Ignition Timing. Refer to
ADJUSTMENT PROCEDURES.



Spark timing Check Spark Controls. Refer to
COMPUTERIZED ENGINE CONTROLS.




Restricted exhaust Check the Catalytic Converter
under TESTING PROCEDURES.