Checks
| Action
|
DEFINITION: Fuel economy, as measured by an actual road
test, is noticeably lower than expected.
|
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 as shown on the Vehicle Emission Control Information
label. |
| • | Check the owner's driving habits for the following items: |
| - | The A/C ON full time (Defroster mode ON)? |
| - | The tires for being at the correct air pressure. |
| - | Excessively heavy loads being carried? |
| - | Aggressive driving habits. |
| • | Suggest to the owner to fill the fuel tank and to recheck the
fuel economy. |
| • | Suggest to the driver to refer to Important Facts on Fuel Economy
in the owner's manual. |
|
Fuel System Checks
|
|
Ignition System Checks
|
| • | Check the spark plugs. Remove the spark plugs and check for the
following: |
| • | Check for an open ignition control (IC) circuit. |
| • | Check the ignition wires for the following items: |
| • | Check the knock sensor (KS) system operation. |
|
Cooling System Checks
|
| • | Check the engine coolant level. |
| • | Check the engine thermostat for always being open or for the wrong
heat range. |
|
Additional Checks
|
| • | Check the transmission shift pattern. Refer to the Transmission
Controls section. |
| • | Check for torque converter clutch (TCC) operation. Refer to Torque Converter Diagnosis Procedure (4L60E)
or Torque Converter Diagnosis Procedure (4L680E)
in
Automatic Transmission. |
| • | Check for proper calibration of the speedometer. |
| • | Check for dragging brakes. |
|
