On-Vehicle Inspection [10/2018 - ]: Procedure

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INSPECT ENGINE COOLANT (for Engine)
Refer to ON-VEHICLE INSPECTION [10/2018 - 10/2019] , or refer to ON-VEHICLE INSPECTION [10/2019 - ]
INSPECT ENGINE OIL
Refer to ON-VEHICLE INSPECTION [10/2018 - ]
INSPECT AUXILIARY BATTERY
Refer to ON-VEHICLE INSPECTION [10/2018 - ]
INSPECT SPARK PLUG
Refer to ON-VEHICLE INSPECTION [10/2018 - ]
INSPECT AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY
1. Remove the air cleaner filter element sub-assembly.
2. Visually check that the air cleaner filter element sub-assembly is not damaged or excessively oily.
  HINT:
  - If there is any dirt or clogs in the air cleaner filter element sub-assembly, clean it with compressed air.
  - If any dirt or clogs remain even after cleaning the air cleaner filter element sub-assembly with compressed air, replace it.
3. Install the air cleaner filter element sub-assembly.
INSPECT VALVE LASH ADJUSTER ASSEMBLY NOISE
1. Put the engine in inspection mode.
  Refer to INSPECTION MODE PROCEDURE [10/2018 - ]
2. Rev up the engine several times. Check that the engine does not emit unusual noises.
3. If unusual noises occur, warm up the engine and idle it for 30 minutes or more, then perform the inspection.
  HINT:
  
  If any defects or problems are found during the inspection, perform the valve lash adjuster assembly inspection.
  
  Refer to PROCEDURE - Step 21

INSPECT IGNITION TIMING

NOTE:

Check the ignition timing with the cooling fan off.
Turn off all electrical systems and the A/C.
When checking the ignition timing, the transaxle should be in park.

Put the engine in inspection mode.
Refer to INSPECTION MODE PROCEDURE [10/2018 - ]
Warm up and stop the engine.
Connect the Techstream to the DLC3.
Put the engine in inspection mode.
Refer to INSPECTION MODE PROCEDURE [10/2018 - ]

Enter the following menus: Powertrain / Engine / Data List / Ignition Timing Cylinder #1.

Powertrain > Engine > Data List

Tester Display
Ignition Timing Cylinder #1

Standard Ignition Timing

0 to 15° BTDC at idle

Check that the ignition timing advances immediately when the engine speed is increased.

Enter the following menus: Powertrain / Engine / Active Test / Activate the TC Terminal / ON.

Powertrain > Engine > Active Test

Active Test Display
Activate the TC Terminal

Data List Display
Ignition Timing Cylinder #1

Monitor Ignition Timing Cylinder #1 of the Data List.
Standard Ignition Timing

8 to 12° BTDC at idle

INSPECT ENGINE IDLE SPEED

NOTE:

Check the ignition timing with the cooling fan off.
Turn off all electrical systems and the A/C.
When checking the ignition timing, the transaxle should be in park.

Put the engine in inspection mode.
Refer to INSPECTION MODE PROCEDURE [10/2018 - ]
Warm up and stop the engine.
Put the engine in inspection mode.
Refer to INSPECTION MODE PROCEDURE [10/2018 - ]

Enter the following menus: Powertrain / Engine / Data List / Engine Speed.

Powertrain > Engine > Data List

Tester Display
Engine Speed

Read the value displayed on the Techstream.
Standard Idle Speed

1050 to 1150 rpm

INSPECT COMPRESSION

NOTE:

Keep the spark plug holes free of foreign matter when measuring the compression pressure.

Put the engine in inspection mode.
Refer to INSPECTION MODE PROCEDURE [10/2018 - ]
Warm up and stop the engine.
Check for DTCs.
Refer to DTC CHECK / CLEAR [10/2018 - ]
Remove the 4 spark plugs.
Refer to REMOVAL [10/2018 - ]

NOTE:
DTCs will be stored if the inspection is performed with the ignition coil assembly connectors disconnected. Make sure that the ignition coil assembly connectors are connected during the inspection.

Disconnect the No. 5 engine wire connector.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Remove the No. 1 engine under cover.
See step [10/2018 - 07/2022] 6, or see step [07/2022 - ] 5

Disengage the claw and raise the lock lever to disconnect the No. 6 engine wire connector as shown in the illustration.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Lock Lever

Check the cylinder compression pressure.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Insert a compression gauge into the spark plug hole.
Connect the Techstream to the DLC3.
Turn the power switch on (IG).
Turn the Techstream on.
NOTE:
Check the HV battery voltage in the Data List to ensure that the battery is fully charged.

Enter the following menus: Powertrain / Hybrid Control / Active Test / Compression Test / ON.

Powertrain > Hybrid Control > Active Test

Tester Display
Compression Test

Depress and hold the brake pedal, and turn the power switch on (READY). Then check the compression pressure.
Standard Compression Pressure

1400 kPa (14.3 kgf/cm² , 203 psi)

Minimum Compression Pressure

800 kPa (8.2 kgf/cm² , 116 psi)

Pressure Difference between Each Cylinder

200 kPa (2.0 kgf/cm² , 29 psi) or less
NOTE:
- Noise may be emitted from the hybrid vehicle transaxle assembly. However, this is not a malfunction.
- Inspect all cylinders in the same way.
- Measure the compression pressure as quickly as possible.
If the cylinder compression pressure is low, pour a small amount of engine oil into the cylinder through the spark plug hole and inspect it again.
HINT:
- If adding oil increases the compression pressure, the piston rings and/or cylinder bore may be worn or damaged.
- If the compression pressure stays low, a valve may be stuck or seated improperly, or there may be leaks in the cylinder head gasket.

Connect the No. 6 engine wire connecto and push down the lock lever to engage the claw as shown in the illustration.

*a	Lock Lever

Install the No. 1 engine under cover.
See step 67, or refer to PROCEDURE - Step 67

Connect the No. 5 engine wire connector.

Install the 4 spark plugs.
Refer to INSTALLATION [10/2018 - ]
Clear the DTCs.
Refer to DTC CHECK / CLEAR [10/2018 - ]

NOTE:
After performing the inspection, clear the DTCs and confirm that DTCs are not stored again or that the normal system code is output if using a check wire.

INSPECT CO/HC

HINT:

This check determines whether or not the idle CO/HC complies with regulations.

Put the engine in inspection mode.
Refer to INSPECTION MODE PROCEDURE [10/2018 - ]
Run the engine speed at 2500 rpm for approximately 180 seconds.
Insert a CO/HC meter testing probe at least 40 cm (1.31 ft.) into the tailpipe during idle.

Immediately check the CO/HC concentration at idle and then at an engine speed of 2500 rpm.

HINT:

When performing a 2 mode test (with the engine idling/running at 2500 rpm), the measurement procedures are determined by applicable local regulations.

If the CO/HC concentration does not comply with the regulations, perform troubleshooting in the order given below.

Check for DTCs.
Refer to DTC CHECK / CLEAR [10/2018 - ]

See the following table for possible causes, then inspect the applicable parts and repair them if necessary.

CO	HC	Problem	Cause
Normal	High	Rough idle	Faulty ignition: Incorrect valve timing Fouled, shorted or improperly gapped spark plugs Incorrect valve clearance (valve lash adjuster assembly) Leaks in intake or exhaust valves Leaks in cylinders Faulty EGR
Low	High	Rough idle (Fluctuating HC reading)	Vacuum leaks: PCV hoses Intake manifold Throttle body with motor assembly Lean mixture causing misfire Faulty EGR
High	High	Rough idle (Black smoke from exhaust)	Restricted air cleaner filter element sub-assembly Plugged PCV valve Faulty SFI systems: Fuel pressure regulator assembly Engine coolant temperature sensor Mass air flow meter ECM Fuel injector assemblies Throttle position sensor (built into throttle body with motor assembly) Faulty EGR