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Engine Control System [Mzr 2.5]: Removal & Installation Mazda 6 GJ

Testing & Diagnostics 14 illustrations ~968 words

ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [MZR 2.5]

WARNINGWhen the engine is hot, it can badly burn. Turn off the engine and wait until it is cool before removing the ECT sensor.

Scheme 19

Scheme 19
Scheme 19
  1. Disconnect the negative battery cable. (See «BATTERY REMOVAL/INSTALLATION [MZR 2.5]»(ref-581638-S19258420632013101400000).)
  2. Drain the engine coolant. (See «ENGINE COOLANT REPLACEMENT [MZR 2.5]»(ref-581646-S28004987162013101400000).)
  3. Remove the battery and battery tray. (See «BATTERY REMOVAL/INSTALLATION [MZR 2.5]»(ref-581638-S19258420632013101400000).)
  4. Disconnect the ECT sensor connector.
  5. Remove the ECT sensor. (Scheme 19): Identifying ECT Sensor With Torque Specification
  6. Install in the reverse order of removal.
  7. Refill the engine coolant. (See «ENGINE COOLANT REPLACEMENT [MZR 2.5]»(ref-581646-S28004987162013101400000).)

Scheme 20

Scheme 20: ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION [MZR 2.5]
Scheme 20: ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION [MZR 2.5]
  1. Disconnect the negative battery cable. (See «BATTERY REMOVAL/INSTALLATION [MZR 2.5]»(ref-581638-S19258420632013101400000).)
  2. Drain the engine coolant. (See «ENGINE COOLANT REPLACEMENT [MZR 2.5]»(ref-581646-S28004987162013101400000).)
  3. Remove the battery and battery tray. (See «BATTERY REMOVAL/INSTALLATION [MZR 2.5]»(ref-581638-S19258420632013101400000).)
  4. Disconnect the ECT sensor connector.
  5. Remove the ECT sensor. (See «ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [MZR 2.5]»(ref-581641-S30062409372013101400000).)
  6. Place the ECT sensor in water with a thermometer, and heat the water gradually.
  7. Measure the resistance between ECT sensor terminals A and B. (Scheme 20): Identifying ECT Sensor Connector Terminals If not as specified, replace the ECT sensor. (See «ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [MZR 2.5]»(ref-581641-S30062409372013101400000).)

BAROMETRIC PRESSURE (BARO) SENSOR REMOVAL/INSTALLATION [MZR 2.5]

Note. The BARO sensor cannot be removed as a single unit. When replacing the BARO sensor, replace it together with the PCM as a single unit.

  1. Remove the PCM. (See «PCM REMOVAL/INSTALLATION [MZR 2.5]»(ref-581641-S36222280212013101400000) .)

AIR FUEL RATIO (A/F) SENSOR REMOVAL/INSTALLATION [MZR 2.5]

WARNINGA hot engine and exhaust system can cause severe burns. Turn off the engine and wait until they are cool before removing the exhaust system.

Scheme 21

Scheme 21
Scheme 21
  1. Disconnect the negative battery cable. (See «BATTERY REMOVAL/INSTALLATION [MZR 2.5]»(ref-581638-S19258420632013101400000).)
  2. Remove the plug hole plate. (See «PLUG HOLE PLATE REMOVAL/INSTALLATION [MZR 2.5]»(ref-581643-S18902301812013101400000).)
  3. Disconnect the A/F sensor connector.
  4. Remove the A/F sensor using the SST. (Scheme 21): A/F Sensor And Removal Tool With Torque Specifications
  5. Install in the reverse order of removal.

Scheme 22

Scheme 22: A/F Sensor Inspection
Scheme 22: A/F Sensor Inspection
  1. Warm up the engine to normal operating temperature.
  2. Access the following PIDs using the M-MDS: (See «ON-BOARD DIAGNOSTIC TEST [MZR 2.5]»(ref-581633-S34331335932013101400000).) VSS (Vehicle speed) RPM (Engine speed) O2S11 (A/F sensor output current)
  3. Drive the vehicle and decelerate the engine speed by releasing the accelerator pedal fully when the engine speed is 3,000 rpm or more.
  4. Verify that the A/F sensor current (PID: O2S11) is 0.25 mA or more while decelerating as shown in the figure. (Scheme 22): Air Fuel Ratio (A/F) Sensor Graph For Speed If not within the specification, replace the A/F sensor. (See «AIR FUEL RATIO (A/F) SENSOR REMOVAL/INSTALLATION [MZR 2.5]»(ref-581641-S29186086582013101400000).)

Scheme 23

Scheme 23: A/F Sensor Heater Inspection
Scheme 23: A/F Sensor Heater Inspection
  1. Disconnect the negative battery cable. (See «BATTERY REMOVAL/INSTALLATION [MZR 2.5]»(ref-581638-S19258420632013101400000).)
  2. Disconnect the A/F sensor connector.
  3. Measure the resistance between A/F sensor terminals A and E. (Scheme 23): Identifying A/F Sensor Connector Terminals If not as specification, replace the A/F sensor. (See «AIR FUEL RATIO (A/F) SENSOR REMOVAL/INSTALLATION [MZR 2.5]»(ref-581641-S29186086582013101400000).) A/F sensor heater resistance 1-10 ohms

HEATED OXYGEN SENSOR (HO2S) REMOVAL/INSTALLATION [MZR 2.5]

WARNINGA hot engine and exhaust system can cause severe burns. Turn off the engine and wait until they are cool before removing the exhaust system.

Scheme 24

Scheme 24
Scheme 24
  1. Disconnect the negative battery cable. (See «BATTERY REMOVAL/INSTALLATION [MZR 2.5]»(ref-581638-S19258420632013101400000).)
  2. Remove the plug hole plate. (See «PLUG HOLE PLATE REMOVAL/INSTALLATION [MZR 2.5]»(ref-581643-S18902301812013101400000).)
  3. Disconnect the HO2S connector.
  4. Remove the HO2S using the SST. (Scheme 24): HO2S And Removal Tool With Torque Specifications
  5. Install in the reverse order of removal.

Scheme 25

Scheme 25: HO2S Inspection
Scheme 25: HO2S Inspection
  1. Warm up the engine to normal operating temperature.
  2. Access the following PIDs using the M-MDS: (See «ON-BOARD DIAGNOSTIC TEST [MZR 2.5]»(ref-581633-S34331335932013101400000).) VSS (Vehicle speed) RPM (Engine speed) O2S12 (HO2S voltage)
  3. Drive the vehicle and decelerate the engine speed by releasing the accelerator pedal fully when the engine speed is 3,000 rpm or more.
  4. Verify that the HO2S voltage (PID: O2S12) of 0.6 V or more, one time or more, then verify that the HO2S voltage (PID: O2S12) is 0.3 V or less while decelerating as shown in the figure. (Scheme 25): Heated Oxygen Sensor Speed Graph If not as specified, replace the HO2S. (See «HEATED OXYGEN SENSOR (HO2S) REMOVAL/INSTALLATION [MZR 2.5]»(ref-581641-S26609355392013101400000).)

Scheme 26

Scheme 26: HO2S Heater Inspection
Scheme 26: HO2S Heater Inspection
  1. Disconnect the negative battery cable. (See «BATTERY REMOVAL/INSTALLATION [MZR 2.5]»(ref-581638-S19258420632013101400000).)
  2. Disconnect the HO2S connector.
  3. Measure the HO2S resistance between terminals C and D. (Scheme 26): Identifying HO2S Connector Terminals If not as specified, replace the HO2S. (See «HEATED OXYGEN SENSOR (HO2S) REMOVAL/INSTALLATION [MZR 2.5]»(ref-581641-S26609355392013101400000).) HO2S heater resistance 2-50 ohms

Scheme 27

Scheme 27: Removal
Scheme 27: Removal
  1. Disconnect the negative battery cable. (See «BATTERY REMOVAL/INSTALLATION [MZR 2.5]»(ref-581638-S19258420632013101400000).)
  2. Perform the following procedure for easier access. Remove the aerodynamic under cover No.2. (See «AERODYNAMIC UNDER COVER NO.2 REMOVAL/INSTALLATION»(ref-581657-S19487724012013101400000).) Remove the splash shield. (See «SPLASH SHIELD REMOVAL/INSTALLATION»(ref-581657-S33349810032013101400000).)
  3. Disconnect the CKP sensor connector.
  4. Remove the CKP sensor. (Scheme 27): Identifying CKP Sensor With Bolts

Installation

CAUTIONWhen foreign material such as an iron chip is on the CKP sensor, it can cause abnormal output from the sensor because of flux turbulence and adversely affect the engine control. Be sure there is no foreign material on the CKP sensor when replacing. Do not assemble the crankshaft position sensor or change the installation position using any method other than the following. Otherwise, it could negatively affect engine controls, such as the ignition timing and fuel injection.

Scheme 28

Scheme 28
Scheme 28

Scheme 29

Scheme 29
Scheme 29

Scheme 30

Scheme 30
Scheme 30

Scheme 31

Scheme 31
Scheme 31
  1. Perform the following procedure so that cylinder No.1 is at TDC. Remove the wheel and tire (front right side). Disconnect the drive shaft (RH) from joint shaft, set the drive shaft (RH) out of the way. (ATX) (See «DRIVE SHAFT REMOVAL/INSTALLATION»(ref-581658-S27921945112013101400000).) Remove the cylinder block lower blind plug and install the SST. (Scheme 28): Identifying SST (303-507) Rotate the crankshaft pulley clockwise until the crank weight contacts the SST so that cylinder No.1 is at TDC.
  2. Fit the center of the CKP sensor with the fifth tooth (counting counterclockwise from the empty space A as shown in the figure) of the pulse wheel. (Scheme 29): Identifying CKP Sensor Position On Pulse Wheel
  3. Align the center line of the CKP sensor and the line drawn in Step 2, then install the sensor.
  4. Install the CKP sensor fitting bolts. (Scheme 30): Identifying CKP Sensor Fitting Bolts With Torque Specification
  5. Remove the SST then install the cylinder block lower blind plug. (Scheme 31): Identifying Cylinder Block Lower Blind Plug With Torque Specification
  6. Install the drive shaft (RH). (ATX) (See «DRIVE SHAFT REMOVAL/INSTALLATION»(ref-581658-S27921945112013101400000).)

CAMSHAFT POSITION (CMP) SENSOR REMOVAL/INSTALLATION [MZR 2.5]

CAUTIONWhen replacing the CMP sensor, make sure there is no foreign material on it such as metal shavings. If it is installed with foreign material, the sensor output signal will malfunction resulting from fluctuation in magnetic flux and cause a deterioration in engine control.

Scheme 32

Scheme 32
Scheme 32
  1. Disconnect the negative battery cable. (See «BATTERY REMOVAL/INSTALLATION [MZR 2.5]»(ref-581638-S19258420632013101400000).)
  2. Remove the plug hole plate. (See «PLUG HOLE PLATE REMOVAL/INSTALLATION [MZR 2.5]»(ref-581643-S18902301812013101400000).)
  3. Disconnect the CMP sensor connector.
  4. Remove the CMP sensor. (Scheme 32): Identifying CMP Sensor And Bolt With Torque Specification
  5. Install in the reverse order of removal.

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