Checks
| Action
|
Definition:
Fuel economy, as measured by an actual road test, is noticeably lower than
expected. Also, the economy is noticeably lower than it was on this vehicle
at one time, as previously shown by an actual road test.
|
Preliminary Checks
| 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 as shown on the Vehicle Emission Control Information
label. |
| • | Check the driving habits of the owner for the following items: |
| • | The operation of the thermostatic air cleaner |
| - | Is the A/C ON full time (is the Defroster mode ON)? |
| - | Do the tires have the correct air pressure? |
| - | Are excessively heavy loads being carried? |
| - | Is the acceleration too much, too often? |
| • | 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
|
| • | Check the fuel type, quality, and alcohol content. Refer to the
Fuel System section. |
|
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. Refer to Knock Sensor (KS) System Diagnosis (Overview)
. |
|
Cooling
System Checks
|
| • | Check the engine coolant level. |
| • | Check the engine thermostat for always being open or for the wrong
heat range. Refer to Diagnosis of the Thermostat in Engine Cooling. |
|
Additional
Checks
|
| • | Check the transmission shift pattern. Refer to the Transmission
Controls section. |
| • | Check for Torque Converter Clutch (TCC) operation. Refer to Torque
Converter Clutch Solenoid in Automatic Transmission. |
| • | Check for proper calibration of the speedometer. |
| • | Check for dragging brakes. Refer to Section 5 of the appropriate
service manual. |
|
