Poor Fuel Economy
***UPDATED BY TSB #405489 DATED FEB. 20, 1989Mazda recommends the use of UNLEADED REGULAR gasoline only, in all vehicles not equipped with a turbocharger, unless otherwise specified. Do not use, or recommend for use, any higher octane fuels. Starting, idle, and driveability problems may result. See factory Technical Service Bulletin #405489, titled "USE OF REGULAR UNLEADED GASOLINE".
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
Rich air/fuel ratio Check air/fuel ratio,
Refer to COMPUTERIZED ENGINE CONTROLS,
Incorrect fuel pressure See FUEL PUMP AND PRESSURE REGULATOR (SYSTEM PRESSURE CHECKS) under COMPONENT TESTING
Speedometer inaccurate Check speedometer calibration
Fuel leak Inspect fuel lines, tank
and fittings