Engine - Intake-Air System: Diagnosis Mazda CX-7 I facelift

INTAKE AIR SYSTEM MANIFOLD VACUUM INSPECTION [L3 WITH TC]

1. Verify that the intake air hoses are installed securely.
2. Warm up the engine.
3. Disconnect the vacuum hose connected between the check valve and the intake manifold from the intake manifold and install the vacuum gauge. (See «QUICK RELEASE CONNECTOR REMOVAL/INSTALLATION [L3 WITH TC]»(ref-343778-S20155531342009101500000) )
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 [L3 WITH TC]»(ref-343774-S27424874312009101500000) ). 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 -71 kPa {-533 mmHg, -21 inHg} or more

AIR CLEANER ELEMENT INSPECTION [L3 WITH TC]

1. Remove the air cleaner element. (See «INTAKE AIR SYSTEM REMOVAL/INSTALLATION [L3 WITH TC]»(ref-343780-S31334616152009101500000) .)
2. Verify that the air cleaner element surface is free of dirt. If there is dirt, use an air gun or similar tool to clean the element. If the replacement time limit has passed, replace the element.

Scheme 152

1. Remove the charge air cooler duct.
2. Remove the charge air cooler cover. (See «INTAKE AIR SYSTEM REMOVAL/INSTALLATION [L3 WITH TC]»(ref-343780-S31334616152009101500000) .)
3. Remove the charge air cooler. (See «INTAKE AIR SYSTEM REMOVAL/INSTALLATION [L3 WITH TC]»(ref-343780-S31334616152009101500000) .)
4. Remove the air bypass valve. (See «INTAKE AIR SYSTEM REMOVAL/INSTALLATION [L3 WITH TC]»(ref-343780-S31334616152009101500000) .)
5. Plug ports A and B.
6. Verify that there is no air leakage when air is sent from port C. If there is leakage, replace the charge air cooler.

Scheme 153

1. Remove the charge air cooler duct.
2. Remove the air bypass valve. (See «INTAKE AIR SYSTEM REMOVAL/INSTALLATION [L3 WITH TC]»(ref-343780-S31334616152009101500000) .)
3. Connect the vacuum pump to the vacuum ports of the air bypass valve.
4. Verify that the airflow is as indicated in the table. If there is any malfunction, replace the air bypass valve.

Approx. value

Scheme 154

THROTTLE ACTUATOR INSPECTION [L3 WITH TC]

Note. Perform the following inspection only when directed.

Resistance Inspection

1. Disconnect the negative battery cable.
2. Disconnect the throttle body connector.
3. Measure the resistance between the throttle actuator terminals using a tester. If not as specified, replace the throttle body. (See «INTAKE AIR SYSTEM REMOVAL/INSTALLATION [L3 WITH TC]»(ref-343780-S31334616152009101500000) .) If as specified, carry out the "Circuit Open/Short Inspection" below.

Specification

Scheme 155

Scheme 156

1. Disconnect the PCM connector. (See «PCM REMOVAL/INSTALLATION [L3 WITH TC]»(ref-343775-S36886452072009101500000) ).
2. Inspect the following wiring harnesses for an open or short circuit (continuity check).

Open circuit

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. Throttle actuator terminal F and PCM terminal 2A Throttle actuator terminal E and PCM terminal 2B

Short circuit

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. Throttle actuator terminal F and power supply Throttle actuator terminal F and ground Throttle actuator terminal E and power supply Throttle actuator terminal E and ground

Scheme 157

Scheme 158

1. Remove the variable swirl solenoid valve.
2. Inspect the airflow between the ports under the following conditions. If not as specified, replace the variable swirl control solenoid valve. If as specified, carry out the "Circuit Open/Short Inspection".

Scheme 159

Scheme 160

Scheme 161

1. Disconnect the PCM connector. (See «PCM REMOVAL/INSTALLATION [L3 WITH TC]»(ref-343775-S36886452072009101500000) ).
2. Inspect the following wiring harness for open or short circuit (continuity check).

Open circuit

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. Variable swirl solenoid valve terminal B and PCM terminal 2AS Variable swirl solenoid valve terminal A and main relay terminal E

Short circuit

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. Variable swirl solenoid valve terminal A and body ground Variable swirl solenoid valve terminal B and power supply Variable swirl solenoid valve terminal B and body ground

VARIABLE SWIRL SHUTTER VALVE ACTUATOR INSPECTION [L3 WITH TC]

1. Remove the air hose. (See «INTAKE AIR SYSTEM REMOVAL/INSTALLATION [L3 WITH TC]»(ref-343780-S31334616152009101500000) .)
2. Disconnect the vacuum hose from the variable swirl control solenoid valve.
3. Connect a vacuum pump to the variable swirl shutter valve actuator.
4. Apply vacuum and verify that the rod moves. If the rod does not move, replace the intake manifold. (See «INTAKE AIR SYSTEM REMOVAL/INSTALLATION [L3 WITH TC]»(ref-343780-S31334616152009101500000) .)

Scheme 162

Scheme 163

1. Remove the wastegate control solenoid valve. (See «INTAKE AIR SYSTEM REMOVAL/INSTALLATION [L3 WITH TC]»(ref-343780-S31334616152009101500000) .)
2. Inspect the airflow between the ports under the following conditions. If not as specified, replace the wastegate control solenoid valve. If as specified, carry out the "Circuit Open/ Short Inspection".

Scheme 164

Scheme 165

1. Disconnect the PCM connector. (See «PCM REMOVAL/INSTALLATION [L3 WITH TC]»(ref-343775-S36886452072009101500000) ).
2. Inspect the following wiring harness for an open or short circuit (continuity check).

Open circuit

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. Wastegate control solenoid valve terminal B and PCM terminal 2AA Wastegate control solenoid valve terminal A and main relay terminal E

Short circuit

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. Wastegate control solenoid valve terminal A and body ground Wastegate control solenoid valve terminal B and power supply Wastegate control solenoid valve terminal B and body ground

Scheme 166

Scheme 167

1. Remove the air hose and air duct. (See «INTAKE AIR SYSTEM REMOVAL/INSTALLATION [L3 WITH TC]»(ref-343780-S31334616152009101500000) )
2. Disconnect the hose from the wastegate actuator.
3. Plug the wastegate actuator as shown in the figure.
4. Connect the vacuum pump to the port.
5. Raise the pressure slowly and take a measurement of the pressure when the rod stroke is 1.5 mm {0.06 in}. If the rod does not move, replace the turbocharger. Specification (rod stroke: 1.5 mm {0.06 in}) 78.0- 83.4 kPa {586- 625 mmHg, 23.1- 24.6 inHg}

Scheme 168

1. Remove the turbocharger. (See «INTAKE AIR SYSTEM REMOVAL/INSTALLATION [L3 WITH TC]»(ref-343780-S31334616152009101500000) .)
2. Visually inspect the compressor wheel from view A for the cracks, damage, or bending on all the compressor wheel blades. If there are any cracks or damage, replace the turbocharger. NOTE: If there is contact between the compressor wheel and compressor housing, there may be cracks, damage, or bending on the blade end area. If there are cracks, damage, or bending on the compressor wheel, verify the following after replacing the turbocharger. Intake air/exhaust system related components Oil pipe damage

Scheme 169

1. Remove the turbocharger. (See «INTAKE AIR SYSTEM REMOVAL/INSTALLATION [L3 WITH TC]»(ref-343780-S31334616152009101500000) .)
2. Visually inspect the turbine wheel from view B for the cracks, damage, or bending on all the turbine wheel blades. If there are cracks, damage, or bending on the turbine wheel, replace the turbocharger. NOTE: If there is contact between the turbine wheel and turbine housing, there may be cracks, damage, or bending on the blade end area. If there are cracks, damage, or bending on the turbine wheel, verify the following after replacing the turbocharger. Intake air/exhaust system related components Oil pipe damage

Scheme 170

1. Disconnect the negative battery cable.
2. Remove in the order indicated in the table.
3. Install in the reverse order of removal.