Kubota WG1605-E3 Diagnostic Manual page 25

WG1605-G-E3,WG1605-L-E3,WG1605-GL-E3, DM
Checks
DEFINITION: Fuel economy, as measured by refueling records is noticeably lower than expected. Also, the economy is noticeably lower, than
it was on this vehicle at one time as previously shown by refueling records.
Preliminary Checks
Fuel System Checks
Sensor Checks
Ignition System Checks
Cooling System Checks
Engine Mechanical Check
Additional Check
Poor Fuel Economy
• Refer to Important Preliminary Checks.
• Check the air cleaner element (filter) for dirt or being plugged.
• Visually (Physically) check the vacuum hoses for splits, kinks and proper connections.
• Check the operators driving habits for the following items:
– Is there excessive idling or stop and go driving
– Are the tires at the correct air pressure
– Are excessively heavy loads being carried
– Is there often rapid acceleration
• Suggest to the owner to fill the fuel tank and to recheck the fuel economy.
• Suggest that a different operator use the equipment and record the results.
• Check the fuel Rail pressure. Refer to Gasoline Fuel System Diagnosis.
• Check the fuel system for leakage.
• Check the Temperature Manifold Absolute Pressure (TMAP) sensor.
• Verify that the spark plugs are correct.
• Check the spark plugs. Remove the plugs and inspect them for the following conditions:
– Wet plugs
– Cracks
– Wear
– Improper gap
– Burned electrodes
– Heavy deposits
• Check the engine thermostat for always being open or for the wrong heat range.
• Check the engine for the following:
– Engine compression
– Valve timing
– Improper or worn camshaft. Refer to Engine Mechanical, in the Service Manual.
• Check the transmission shift pattern. Refer to the OEM Transmission Controls section in their
Service Manual.
• Check for dragging brakes.
1-15
Action
ECM SYSTEM
KiSC issued 12, 2016 A