COMPRESSION INSPECTION
Warning
1. Verify that the battery is fully charged.
2. Warm up the engine to the normal operating temperature.
3. Stop the engine and allow it to cool off for about 10 min.
4. Perform Fuel Line Safety Procedures. Leave the fuel pump relay removed.
(See BEFORE REPAIR
PROCEDURE.)
Warning
5. Remove the ignition coil connector.
6. Remove the spark plugs. (See SPARK PLUG REMOVAL/INSTALLATION.)
7. Connect a compression gauge into the spark plug hole.
8. Fully depress the accelerator pedal and crank the engine.
9. Note the maximum gauge reading.
10. Inspect each cylinder as above.
or more, add a small amount of engine oil through the spark plug hole. Then measure the compression pressure and perform the respective operations for the following cases.
- If the compression increases, the piston, the piston rings, or cylinder wall may be worn and overhaul is required.
- If the compression stays low, a valve may be stuck or improperly seated and overhaul is required.
- If the compression in adjacent cylinders stays low, the cylinder head gasket may be damaged or the cylinder head distorted and overhaul is required.
Compression
kPa {kgf/cm2, psi} [rpm]
kPa {kgf/cm2, psi} [rpm]
kPa {kgf/cm2, psi} [rpm]
11. Disconnect the compression gauge.
12. Install the spark plugs. (See SPARK PLUG REMOVAL/INSTALLATION.)
13. Connect the ignition coil connector.
14. Install the fuel pump relay. (See BEFORE REPAIR PROCEDURE.)
Mazda 6 Service Manual: Foreword
When the customer reports a vehicle malfunction, check the malfunction
indicator lamp (MIL) indication and diagnostic trouble code (DTC), then
diagnose the malfunction according to following flowchart.
- If a DTC exists, diagnose the applicable DTC inspection. (See DTC
TABLE.)
- ...
Mazda 6 Service Manual: Fuel Requirements
Vehicles with catalytic converters or oxygen sensors must use ONLY UNLEADED FUEL,
which will reduce exhaust emissions and keep spark plug fouling to a minimum.
This vehicle will perform best with fuel listed in the table.
* U.S. federal law requires that octane ratings be posted on gasoline st ...