Engine - Intake-Air System: Diagnosis Mazda 3 BK

INTAKE-AIR SYSTEM MANIFOLD VACUUM INSPECTION [LF]

1. Verify that the intake air hoses are installed securely.
2. Warm up the engine.
3. Disconnect the vacuum hose connecting the intake manifold and the purge solenoid valve (purge solenoid valve side) and install the vacuum gauge. (See PURGE SOLENOID VALVE REMOVAL/INSTALLATION .)
4. Measure the intake manifold vacuum while idling (no load) using the vacuum gauge. If not within the specification, perform the following inspections. Accelerator cable play Compression pressure (See COMPRESSION INSPECTION .) Air suction (installation areas of throttle body, fuel injector, PCV valve, intake manifold) NOTE: If any air suction exists, the change in engine speed can be made apparent by spraying the penetrant lubricating spray on the applicable part. Standard ATX: -55.0 kPa {-413 mmHg, -16.3 inHg} or more MTX: -57.0 kPa {-428 mmHg, -16.9 inHg} or more

INTAKE-AIR SYSTEM MANIFOLD VACUUM INSPECTION [L3]

1. Verify that the intake air hoses are installed securely.
2. Warm up the engine.
3. Disconnect the vacuum hose connecting the intake manifold and the purge solenoid valve (purge solenoid valve side) and install the vacuum gauge. (See PURGE SOLENOID VALVE REMOVAL/INSTALLATION .)
4. Measure the intake manifold vacuum while idling (no load) using the vacuum gauge. If not within the specification, perform the following inspections. Accelerator cable play Compression pressure (See COMPRESSION INSPECTION .) Air suction (installation areas of throttle body, fuel injector, PCV valve, intake manifold) NOTE: If any air suction exists, the change in engine speed can be made apparent by spraying the penetrant lubricating spray on the applicable part. Standard ATX: -57.0 kPa {-428 mmHg, -16.9 inHg} or more MTX: -60.0 kPa {-451 mmHg, -17.8 inHg} or more

AIR CLEANER ELEMENT INSPECTION

1. Remove the air cleaner element. (See «INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [LF]»(ref-177563-S27802206012005060200000) .) (See «INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3]»(ref-177563-S01004479692005060200000) .)
2. Inspect the following items: If there is any abnormality, clean or replace the air cleaner element. Has the replacement interval come? Is the air cleaner element soiled, damaged, or bent? Are the air cleaner case and the air cleaner element correctly sealed? Is the correct air cleaner element installed?

THROTTLE BODY INSPECTION

Note. Perform the following inspection only when directed.

Scheme 140

1. Disconnect the negative battery cable.
2. Disconnect the throttle body connector.
3. Measure the resistance between throttle actuator terminals E and F. If not as specified, replace the throttle body. (See «INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [LF]»(ref-177563-S27802206012005060200000) .) (See «INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3]»(ref-177563-S01004479692005060200000) .) If as specified, carry out the «Circuit Open/Short Inspection»(ref-177563-S09319200582005060200000) .

Scheme 141

Scheme 142

1. Disconnect the PCM connector. (See «PCM REMOVAL/INSTALLATION»(ref-177569-S38589701122005060200000) .)
2. Inspect the following wiring harnesses for open or short (continuity check).