Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM10000000260T4
Model Year Start: 2023 Model: GR Corolla Prod Date Range: [09/2022 -           ]
Title: G16E-GTS (ENGINE MECHANICAL): ENGINE: ON-VEHICLE INSPECTION; 2023 - 2025 MY GR Corolla [09/2022 -        ]

ON-VEHICLE INSPECTION

CAUTION / NOTICE / HINT

CAUTION:

  • When working near the engine room while the engine has started or the power source mode is engine switch on (IG), do not touch the fan and generator V belt or rotating components such as the fan, etc.
  • Touching the fan and generator V belt or rotating components such as the fan, etc. could result in your hand or clothing getting caught and pulled in.

PROCEDURE

1. INSPECT ENGINE COOLANT

Click here 2023 - 2025 MY GR Corolla [09/2022 -        ]; G16E-GTS (COOLING): COOLING SYSTEM: ON-VEHICLE INSPECTION

2. INSPECT ENGINE OIL

Click here 2023 MY GR Corolla [09/2022 - 08/2023]; G16E-GTS (LUBRICATION): LUBRICATION SYSTEM: ON-VEHICLE INSPECTION 2024 - 2025 MY GR Corolla [08/2023 -        ]; G16E-GTS (LUBRICATION): LUBRICATION SYSTEM: ON-VEHICLE INSPECTION

3. INSPECT AUXILIARY BATTERY CONDITION

Click here 2023 - 2025 MY GR Corolla [09/2022 -        ]; G16E-GTS (BATTERY / CHARGING): CHARGING SYSTEM: ON-VEHICLE INSPECTION

4. INSPECT SPARK PLUG

Click here 2023 - 2025 MY GR Corolla [09/2022 -        ]; G16E-GTS (ENGINE CONTROL): IGNITION SYSTEM: ON-VEHICLE INSPECTION

5. INSPECT AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY

(a) Remove the air cleaner filter element sub-assembly.

Click here 2023 MY GR Corolla [09/2022 - 11/2022]; MAINTENANCE: G16E-GTS DRIVE BELT: REMOVAL 2023 - 2025 MY GR Corolla [11/2022 -        ]; MAINTENANCE: G16E-GTS DRIVE BELT: REMOVAL

(b) Visually check that the air cleaner filter element sub-assembly is not damaged or excessively oily. If necessary, replace the air cleaner filter element sub-assembly.

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.

(c) Install the air cleaner filter element sub-assembly.

Click here 2023 MY GR Corolla [09/2022 - 11/2022]; MAINTENANCE: G16E-GTS DRIVE BELT: INSTALLATION 2023 - 2025 MY GR Corolla [11/2022 -        ]; MAINTENANCE: G16E-GTS DRIVE BELT: INSTALLATION

6. INSPECT FAN AND GENERATOR V BELT

Click here 2023 - 2025 MY GR Corolla [09/2022 -        ]; G16E-GTS (ENGINE MECHANICAL): DRIVE BELT: ON-VEHICLE INSPECTION

7. INSPECT V-RIBBED BELT TENSIONER ASSEMBLY

(a) Remove the fan and generator V belt.

Click here 2023 MY GR Corolla [09/2022 - 11/2022]; MAINTENANCE: G16E-GTS DRIVE BELT: REMOVAL 2023 - 2025 MY GR Corolla [11/2022 -        ]; MAINTENANCE: G16E-GTS DRIVE BELT: REMOVAL

(b) Turn the V-ribbed belt tensioner assembly clockwise and counterclockwise and check that it turns smoothly and does not catch.

HINT:

If the V-ribbed belt tensioner assembly does not turn smoothly or catches, replace the V-ribbed belt tensioner assembly.

(c) Install the fan and generator V belt.

Click here 2023 MY GR Corolla [09/2022 - 11/2022]; MAINTENANCE: G16E-GTS DRIVE BELT: INSTALLATION 2023 - 2025 MY GR Corolla [11/2022 -        ]; MAINTENANCE: G16E-GTS DRIVE BELT: INSTALLATION

8. INSPECT VALVE LASH ADJUSTER ASSEMBLY NOISE

(a) Rev up the engine several times. Check that the engine does not emit unusual noises.

(b) 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.

Click here 2023 - 2025 MY GR Corolla [09/2022 -        ]; G16E-GTS (ENGINE MECHANICAL): ENGINE UNIT: INSPECTION+

9. INSPECT IGNITION TIMING

NOTICE:

  • 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 neutral or park.

(a) Warm up and stop the engine.

(b) Connect the Techstream to the DLC3.

(c) Start the engine and run it at idle.

(d) Turn the Techstream on.

(e) 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:

Condition

Specified Condition

Idle speed

-5 to 15°CA BTDC

(f) 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

(g) Monitor Ignition Timing Cylinder #1 of the Data List.

Standard Ignition Timing:

Condition

Specified Condition

Idle speed

8 to 12°CA BTDC

(h) Enter the following menus: Powertrain / Engine / Active Test / Activate the TC Terminal / OFF.

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

10. INSPECT ENGINE IDLE SPEED

NOTICE:

  • Check the engine idle speed with the cooling fan off.
  • Turn off all electrical systems and the A/C.
  • When checking the engine idle speed, the transaxle should be in neutral.

(a) Warm up and stop the engine.

(b) Connect the Techstream to the DLC3.

(c) Start the engine and run it at idle.

(d) Turn the Techstream on.

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

Powertrain > Engine > Data List

Tester Display

Engine Speed

(f) Read the value displayed on the tester.

Standard Idle Speed:

Condition

Specified Condition

N Position

950 to 1050 rpm

11. INSPECT COMPRESSION

NOTICE:

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

(a) Warm up and stop the engine.

(b) Check for DTCs.

Click here 2023 - 2025 MY GR Corolla [09/2022 -        ]; G16E-GTS (ENGINE CONTROL): SFI SYSTEM: DTC CHECK / CLEAR

(c) Remove the 3 spark plugs.

Click here 2023 - 2025 MY GR Corolla [09/2022 -        ]; MAINTENANCE: G16E-GTS SPARK PLUG: REMOVAL

(d) Disconnect the No. 5 engine wire connector.

(e) Disconnect the No. 6 engine wire connector.

(f) Check the cylinder compression pressure.

(1) Insert a compression gauge into the spark plug hole.

(2) Fully open the throttle.

(3) While cranking the engine, measure the compression pressure.

Standard Compression Pressure:

Item

Minimum Compression Pressure

Standard Compression Pressure

No.1 Cylinder

980 kPa

10.0 kgf/cm2

142 psi

1300 kPa

13.3 kgf/cm2

189 psi

No.2 Cylinder

980 kPa

10.0 kgf/cm2

142 psi

1300 kPa

13.3 kgf/cm2

189 psi

No.3 Cylinder

980 kPa

10.0 kgf/cm2

142 psi

1300 kPa

13.3 kgf/cm2

189 psi

Pressure Difference between Each Cylinder

-

200 kPa or less

2.0 kgf/cm2 or less

29 psi or less

NOTICE:

  • Always use a fully charged auxiliary battery to obtain an engine speed of 250 rpm or more.
  • Inspect all cylinders in the same way.
  • Measure the compression pressure as quickly as possible.

(4) 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 engine 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.

(g) Connect the No. 6 engine wire connector.

(h) Connect the No. 5 engine wire connector.

(i) Install the 3 spark plugs.

Click here 2023 - 2025 MY GR Corolla [09/2022 -        ]; MAINTENANCE: G16E-GTS SPARK PLUG: INSTALLATION

(j) Clear the DTCs.

Click here 2023 - 2025 MY GR Corolla [09/2022 -        ]; G16E-GTS (ENGINE CONTROL): SFI SYSTEM: DTC CHECK / CLEAR

NOTICE:

After the inspection, clear the DTCs, check for DTCs again and make sure the normal system code is output.

12. INSPECT CO/HC

HINT:

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

(a) Start the engine.

(b) Run the engine at 2500 rpm for approximately 180 seconds.

(c) Insert a CO/HC meter testing probe at least 40 cm (1.31 ft.) into the tailpipe during idle.

(d) Immediately check the CO/HC concentration during idle and when the engine is running at 2500 rpm.

HINT:

When performing a 2 mode (with the engine idling/running at 2500 rpm) test, 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.

(1) Check for DTCs.

Click here 2023 - 2025 MY GR Corolla [09/2022 -        ]; G16E-GTS (ENGINE CONTROL): SFI SYSTEM: DTC CHECK / CLEAR

(2) 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

  1. Faulty ignition:
    • Incorrect valve timing
    • Fouled, shorted or improperly gapped spark plugs
  2. Incorrect valve clearance (valve lash adjuster assembly)
  3. Leaks in intake or exhaust valves
  4. Leaks in cylinders

Low

High

Rough idle (Fluctuating HC reading)

  1. Vacuum leaks:
    • PCV hoses
    • Intake manifold
    • Throttle body with motor assembly
  2. Lean mixture causing misfire

High

High

Rough idle (Black smoke from exhaust)

  1. Restricted air cleaner filter element sub-assembly
  2. Plugged PCV valve
  3. 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)