Emission System: Other Mazda 3 BK

Quick Release Connector Type

Scheme 45

Scheme 46

Without using the SST

Scheme 47

1. Release the locks between the retainer and joint port by pressing each retainer lock one by one using a flathead screwdriver or a similar tool.
2. Pull out the hose straight from the joint port and disconnect it. The retainer remains on the joint port.
3. Cover the disconnected quick release connector and joint port with vinyl sheeting or a similar material to prevent it from becoming scratched or dirty.

Scheme 48

1. Move the retainer upward using a small flathead screwdriver or a similar tool.
2. Pull out the evaporative hose straight from the joint port and disconnect it.
3. Cover the disconnected quick release connector and joint port with vinyl sheeting or a similar material to prevent it from becoming scratched or dirty.

Scheme 49

1. Squeeze the release tab until the locks are released.
2. Pull the quick release connector straight outward.
3. Cover the disconnected quick release connector and joint port with vinyl sheeting or a similar material to prevent it from becoming scratched or dirty.

Scheme 50

Scheme 51

1. Squeeze the locking coupler until the locking tab opens and releases. NOTE: The locking coupler has two internal locking tabs which retain the joint port. Be sure that the squeezing place on the locking coupler is squeezed until it can be released from the joint port.
2. Pull the quick release connector straight outward.
3. Cover the disconnected quick release connector and joint port with vinyl sheeting or a similar material to prevent it from becoming scratched or dirty.

Using the SST

1. Inspect the evaporative hose and joint port sealing surface for damage and deformation. If there is any malfunction, replace it with a new one.
2. Reconnect the evaporative hose straight to the joint port until a click is heard.
3. Lightly pull and push the quick release connector a few times by hand, and then verify that it is connected securely.

1. Remove the retainer remaining on the joint port.
2. Install a new retainer to the quick release connector.
3. Reconnect the evaporative hose straight to the joint port until a click is heard.
4. Lightly pull and push the quick release connector a few times by hand, and then verify that it is connected securely.

Without using WDS or equivalent

1. Inspect the following: EGR pipe clogging PCM terminal voltage EGR valve signal Vehicle speed signal Throttle opening signal Engine coolant temperature signal EGR valve (If it is stuck or not moving smoothly, replace it with a new one.)

Scheme 52

1. Connect the WDS or equivalent to the DLC-2.
2. Start the engine.
3. Using the "SEGRP" simulation function, operate with Steps 0 (idling) to 52 and verify that the engine speed becomes unstable or the engine stalls. If the engine speed does not change, perform the following procedure: Stop the engine. Remove the EGR valve. (See «EGR VALVE REMOVAL/INSTALLATION»(ref-177566-S23892591322005060200000) .) Connect the EGR valve connector. Turn the ignition switch to the ON position. Using the "SEGRP" simulation function, verify that it operates with Steps 0 (idling) to 52. If the EGR valve operates, inspect the following: EGR pipe clogging If the EGR valve does not operate, inspect the following: PCM terminal voltage EGR valve signal EGR valve (If it is stuck or not moving smoothly, replace it with a new one.) Warm up the engine to normal operating temperature. Place the vehicle on the chassis dynamometer. Monitor the following signals using the PID/data monitor. EGR valve step number (SEGRP) Engine speed (RPM) Vehicle speed (VSS) Throttle position (TP) Engine coolant temperature (ECT) Verify that the EGR valve step number is 0 during idle. Verify that the EGR valve step number increases when the accelerator pedal is depressed to increase the vehicle speed. If it does not increase, inspect the following using the PID/data monitor. Vehicle speed (VSS) Throttle position (TP) Engine coolant temperature (ECT) Stop the vehicle and verify that the EGR valve step number is 0 during idle.

California Emission Regulation Applicable Models

1. Connect the WDS or equivalent to the DLC-2.
2. Start the engine and warm it up to normal operating temperature.
3. Turn off the engine.
4. Verify that the engine compression is within the specification. (See COMPRESSION INSPECTION .) If the compression pressure is not within the specification, repair or replace the malfunction part.
5. Drive the vehicle for 10 min at 65-96 km/h {40-60 mph} to allow the front catalytic converter to reach operating temperature.
6. Stop the vehicle and leave it in a safe space.
7. Access Test ID 10:21:80 on the "Diagnostic Monitoring Test Result" function.
8. Verify that the test result is within the specified indicated on the WDS or equivalent. If it is not as specified, replace the front catalytic converter.

Except for California Emission Regulation Applicable Models

Note. Make sure that no HO2S DTCs have been detected. If detected, this inspection is not applicable for WU-TWC inspection.

Scheme 53

1. Connect the WDS or equivalent and monitor PIDs as following. Monitor the WU-TWC using O2S11 PID for upstream HO2S and O2S12 PID for downstream HO2S.
2. Monitor the appropriate PIDs.
3. Drive the vehicle for 10 min at 65-96 km/h {40-60 mph} to allow the front catalytic converter to reach operating temperature.
4. Stop the vehicle and leave it in a safe place.
5. Idle the engine.
6. Record PIDs for 1 min.
7. Select the appropriate PIDs and read the graph.
8. Count the number of times (inversions) that the upstream HO2S graph line actually crosses the 0.5 V line.
9. Count the number of times (inversions) that the downstream HO2S graph line actually crosses the 0.5 V line. NOTE: Do not count the number of peaks. Refer to the graph.
10. Using the following equation, calculate the value of ratio. Equation RATIO = Upstream HO2S inversion / downstream HO2S inversion If the ratio is 1.5 or more or there is no downstream HO2S inversion, the WU-TWC is functioning properly. If the ratio is less than 1.5, the WU-TWC is not functioning properly. Replace the WU-TWC.

Scheme 54

Scheme 55

1. Equation
2. RATIO = 30 inversions (upstream HO2S inversions) / 5 inversions (downstream HO2S inversions) = 6.0 (good WU-TWC)

Scheme 56

Scheme 57

1. Equation
2. RATIO = 30 inversions (upstream HO2S inversions) / 27 inversions (downstream HO2S inversions) = 1.1 (bad WU-TWC)