Toyota Prius: Engine

Toyota Prius (XW60) 2023-2025 Service Manual / Engine/Hybrid System / 2zr-fxe (engine Mechanical) / Engine

On-vehicle Inspection

On-vehicle Inspection

ON-VEHICLE INSPECTION

CAUTION / NOTICE / HINT

CAUTION:

To prevent injury due to contact with an operating cooling fan, keep your hands and clothing away from the cooling fans when working in the engine compartment with the engine running or the ignition switch ON.

PROCEDURE

1. INSPECT COOLANT (for Engine)

HINT:

Click here

2. INSPECT ENGINE OIL

HINT:

Click here

3. CHECK AUXILIARY BATTERY

HINT:

Click here

4. INSPECT SPARK PLUG

HINT:

Click here

5. INSPECT AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY

HINT:

Click here

6. INSPECT VALVE LASH ADJUSTER ASSEMBLY NOISE

(a) Put the engine in inspection mode.

Powertrain > Hybrid Control > Utility

Tester Display
Inspection Mode

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

HINT:

If any defects or problems are found during the inspection, perform valve lash adjuster assembly inspection.

Click here

7. INSPECT IGNITION TIMING

NOTICE:

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

Pre-procedure1

(a) Put the engine in inspection mode.

Powertrain > Hybrid Control > Utility

Tester Display
Inspection Mode

(b) Warm up and stop the engine.

Powertrain > Hybrid Control > Utility

Tester Display
Inspection Mode

Procedure1

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

Powertrain > Engine > Data List

Tester Display
Ignition Timing Cylinder #1

Standard Ignition Timing:

8 to 24° BTDC at idle

Procedure2

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

Procedure3

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

Powertrain > Engine > Active Test

Active Test Display
Activate the TC Terminal

Data List Display
Ignition Timing Cylinder #1

Standard Ignition Timing:

8 to 12° BTDC at idle

Post-procedure1

(g) None

8. INSPECT ENGINE IDLE SPEED

NOTICE:

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

Pre-procedure1

(a) Put the engine in Inspection Mode (Maintenance Mode).

Powertrain > Hybrid Control > Utility

Tester Display
Inspection Mode

(b) Warm up and stop the engine.

Powertrain > Hybrid Control > Utility

Tester Display
Inspection Mode

Procedure1

(d) Read the value displayed on the GTS.

Powertrain > Engine > Data List

Tester Display
Engine Speed

Standard Idle Speed:

950 to 1050 rpm

Post-procedure1

(e) None

9. INSPECT COMPRESSION

NOTICE:

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

Pre-procedure1

(a) Put the engine in Inspection Mode (Maintenance Mode).

Powertrain > Hybrid Control > Utility

Tester Display
Inspection Mode

(b) Warm up and stop the engine.

Powertrain > Engine > Trouble Codes

(d) Remove the 4 spark plugs.

NOTICE:

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.

HINT:

Click here

(e) Remove the air cleaner cap sub-assembly.

HINT:

Click here

(f) Remove the air cleaner hose assembly.

HINT:

Click here

(g) w/ Stud Bolt:

(1) Remove the 2 bolts, 2 nuts and separate the throttle body assembly from the intake manifold.

*A	w/ Stud Bolt
*B	w/o Stud Bolt

(h) w/o Stud Bolt:

(1) Remove the 4 bolts and separate the throttle body assembly from the intake manifold.

Procedure1

(i) Check the cylinder compression pressure.

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

(2) Depress and hold the brake pedal, and turn the ignition switch to ON (READY). Then check the compression pressure.

Powertrain > Hybrid Control > Active Test

Tester Display
Compression Test

Standard Compression Pressure:

Item	Minimum Compression Pressure	Specified Condition	Result
Cylinder 1	617 kPa 6.3 kgf/cm2 89.5 psi	813 kPa 8.3 kgf/cm2 118 psi	kPa kgf/cm2 psi
Cylinder 2	617 kPa 6.3 kgf/cm2 89.5 psi	813 kPa 8.3 kgf/cm2 118 psi	kPa kgf/cm2 psi
Cylinder 3	617 kPa 6.3 kgf/cm2 89.5 psi	813 kPa 8.3 kgf/cm2 118 psi	kPa kgf/cm2 psi
Cylinder 4	617 kPa 6.3 kgf/cm2 89.5 psi	813 kPa 8.3 kgf/cm2 118 psi	kPa kgf/cm2 psi
Pressure Difference between Each Cylinder	-	100 kPa or less 1.0 kgf/cm2 or less 15 psi or less	kPa kgf/cm2 psi

Item

Minimum Compression Pressure

Specified Condition

Result

Cylinder 1

617 kPa

6.3 kgf/cm2

89.5 psi

813 kPa

8.3 kgf/cm2

118 psi

kPa

kgf/cm2

psi

Cylinder 2

617 kPa

6.3 kgf/cm2

89.5 psi

813 kPa

8.3 kgf/cm2

118 psi

kPa

kgf/cm2

psi

Cylinder 3

617 kPa

6.3 kgf/cm2

89.5 psi

813 kPa

8.3 kgf/cm2

118 psi

kPa

kgf/cm2

psi

Cylinder 4

617 kPa

6.3 kgf/cm2

89.5 psi

813 kPa

8.3 kgf/cm2

118 psi

kPa

kgf/cm2

psi

Pressure Difference between Each Cylinder

100 kPa or less

1.0 kgf/cm2 or less

15 psi or less

kPa

kgf/cm2

psi

NOTICE:

Inspect all cylinders in the same way.
Measure the compression pressure as quickly as possible.
Noise may be emitted from the hybrid Toyota Prius vehicle transaxle assembly. However, this is not a malfunction.

(3) 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.

Post-procedure1

(j) w/ Stud Bolt:

(1) Install a new throttle body gasket and the throttle body assembly to the intake manifold with the 2 bolts and 2 nuts.

Torque:

10 N·m {102 kgf·cm, 7 ft·lbf}

NOTICE:

If the throttle body assembly has been struck or dropped, replace it.

(k) w/o Stud Bolt:

(1) Install a new throttle body gasket and the throttle body assembly to the intake manifold with the 4 bolts.

Torque:

10 N·m {102 kgf·cm, 7 ft·lbf}

NOTICE:

If the throttle body assembly has been struck or dropped, replace it.

(l) Install the air cleaner hose assembly.

HINT:

Click here

(m) Install the air cleaner cap sub-assembly.

HINT:

Click here

(n) Install the 4 spark plugs.

HINT:

Click here

(o) Clear the DTCs.

Powertrain > Engine > Trouble Codes

NOTICE:

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.

10. INSPECT CO/HC

HINT:

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

Pre-procedure1

(a) Put the engine in Inspection Mode (Maintenance Mode).

Powertrain > Hybrid Control > Utility

Tester Display
Inspection Mode

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

Procedure1

(d) 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.

(1) Check for DTCs.

Powertrain > Engine > Trouble Codes

(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	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 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 with motor body assembly) Faulty EGR