2ZR-FAE (ENGINE CONTROL): SFI SYSTEM: Rough Idling; 2020 - 2023 MY Corolla [01/2019

Last Modified: 05-13-2024	6.11:8.1.0	Doc ID: RM100000001GKCD
Model Year Start: 2020	Model: Corolla	Prod Date Range: [01/2019 - 11/2022]
Title: 2ZR-FAE (ENGINE CONTROL): SFI SYSTEM: Rough Idling; 2020 - 2023 MY Corolla [01/2019 - 11/2022]

Rough Idling

DESCRIPTION

Problem Symptom	Suspected Area	Trouble Area
Engine speed fluctuation due to abnormal combustion Idle speed too low or high Strong engine vibration due to above symptoms	Ignition malfunction Deviation in air fuel ratio (Excessive or insufficient intake air volume or fuel supply) Insufficient compression Changes in load from another system	Ignition system	Spark plug Ignition coil assembly
		Fuel system	Fuel injector assembly Fuel pump Fuel pump control circuit Fuel line Purge VSV system Fuel quality (existence of foreign matter, degradation)
		Intake and exhaust systems	Mass air flow meter sub-assembly Intake system (Air leaks or deposit accumulation) Throttle body assembly Air fuel ratio sensor Heated oxygen sensor Camshaft timing oil control valve assembly Variable Valve Timing system (VVT system)
		Other control systems	ECM Wire harness or connector Knock control sensor Engine coolant temperature sensor
		Engine	Thermostat Engine assembly Engine mount
		High load from another system	Air conditioning system Power steering system Electrical load signal system CVT system

HINT:

If any other DTCs are output, perform troubleshooting for those DTCs first.
Make sure to reproduce the conditions present when the malfunction occurred.
Using the Techstream, read the Data List to confirm the engine operating conditions. This information can be useful when troubleshooting.
If the problem symptoms do not recur, attempt to reproduce the symptoms and conditions when the malfunction occurred based on the result of the customer problem analysis. Place the priority on confirming the symptoms.

SYMPTOM AND CAUSE OF SYSTEM MALFUNCTION

HINT:

The following are descriptions of the characteristics of each system malfunction. After understanding the link between the causes and symptoms, perform the inspection of each component. Even if the problem symptom does not recur, signs of the malfunction may be found in the Data List.

(a) Ignition system

Spark plug

Main cause of malfunction	Performance degradation (wear, existence of foreign matter, etc.)
Symptom	Engine speed fluctuation due to abnormal combustion
Data List	Cylinder Misfire Count
HINT: If the spark plug of the malfunctioning cylinder is abnormally wet with fuel, a leaking fuel injector assembly is suspected.

Ignition coil assembly

Main cause of malfunction	Internal malfunction
Problem symptom	Engine speed fluctuation due to abnormal combustion
Data List	Cylinder Misfire Count

(b) Fuel system

Fuel injector assembly

Main cause of malfunction	Blockage
Problem symptom	Engine speed fluctuation due to abnormal combustion Idle speed too low or high
Data List	Target Air-Fuel Ratio AF Lambda B1S1 Short FT B1S1 Long FT B1S1 Total FT #1 Fuel System Status #1 A/F Learn Value Idle #1 A/F Learn Value Low #1 A/F Learn Value Mid1 #1 A/F Learn Value Mid2 #1 A/F Learn Value High #1
HINT: If the engine malfunction disappears when the fuel injection volume is increased or decreased using the Control the Injection Volume, the respective cylinder may be malfunctioning.

Fuel system

HINT:

If the air fuel ratio becomes lean only when the engine is running under a high load and at a high engine speed, clogging of the fuel pump or fuel filter is suspected.

Fuel quality

Main cause of malfunction	Fuel degradation due to age or water contamination Low fuel quality Addition of fuel additive
Problem symptom	Engine speed fluctuation due to abnormal combustion Idle speed too low or high Engine is difficult to start

Mass air flow meter sub-assembly

Main cause of malfunction	Performance degradation (existence of foreign matter, etc.)
Problem symptom	Lack of power
Data List	MAF
HINT: If the value of the Data List item "MAF" is abnormal, a malfunction of the mass air flow meter sub-assembly is suspected.

Throttle system

Main cause of malfunction	Inappropriate trim volume adjustment due to accumulation of deposits
Problem symptom	Engine speed fluctuation due to abnormal combustion Idle speed too low or high
Data List	ISC Flow ISC Feedback Value ISC Learning Value Electric Load Feedback Val Air Conditioner FB Val Eng Stall Control FB Flow

Air fuel ratio sensor, Heated oxygen sensor

Main cause of malfunction	Deviation in sensor characteristics
Problem symptom	Abnormal combustion due to deviation of actual air fuel ratio from calculated ratio
Data List	AFS Voltage B1S1 O2S B1S2 Fuel System Status #1

(d) Engine

Engine assembly

Main cause of malfunction	Compression loss Accumulation of deposits (Combustion chamber, intake valve or intake manifold)
Problem symptom	Engine speed fluctuation due to abnormal combustion Idle speed too low or high Hesitation during acceleration or stalling
Data List	Compression Leakage Count Rough Idle Status Plural Cylinders Rough Idle Rough Idle #1 Rough Idle #2 Rough Idle #3 Rough Idle #4
HINT: If deposits have accumulated in the combustion chamber or on an intake valve, the engine may stall when deposits are caught on an intake valve. When performing the Active Test "Check the Cylinder Compression", if the speed of one cylinder is higher than the others, the cylinder may have a compression loss. If deposits accumulate on the intake valves, the supply of fuel may be delayed due to adherence of the fuel to the deposits, causing a rough idle.

(e) CVT system

CVT

Main cause of malfunction	Shift solenoid valve SLU stuck on
Symptom	Engine speed drops or rough idle occurs due to delay in lock-up OFF operation
Data List	Engine Speed SPD (NT) Shift SW Status (D Range)
HINT: If the rough idling occurs during neutral control under idling, CVT system is suspected.

Data List Items Related to Rough Idling

HINT:

Depending on the vehicle model, the applicable Data List items may vary. Data List items other than the ones used in the diagnostic procedure are for reference only.

Engine Speed
MAF
ISC Flow
ISC Feedback Value
ISC Learning Value
Electric Load Feedback Val
Air Conditioner FB Val
Neutral Control
Eng Stall Control FB Flow
Target Air-Fuel Ratio
AF Lambda B1S1
AFS Voltage B1S1
O2S B1S2
Short FT B1S1
Long FT B1S1
Total FT #1
Fuel System Status #1
Cylinder #1 Misfire Count
Cylinder #2 Misfire Count
Cylinder #3 Misfire Count
Cylinder #4 Misfire Count
Compression Leakage Count
Rough Idle Status
Plural Cylinders Rough Idle
Rough Idle #1
Rough Idle #2
Rough Idle #3
Rough Idle #4
A/F Learn Value Idle #1
A/F Learn Value Low #1
A/F Learn Value Mid1 #1
A/F Learn Value Mid2 #1
A/F Learn Value High #1
SPD (NT)
Shift SW Status (D Range)

PROCEDURE

1.	INTERVIEW THE CUSTOMER

(a) Interview the customer for details about the conditions when the rough idle occurred.

HINT:

Depending on the conditions when the rough idle occurred, a malfunction in one of the following areas is suspected.

Problem Symptom	Suspected Area
Hesitation or lack of power occurs during acceleration, regardless of whether engine is cold or warm	For low mileage vehicles (ODO reading of less than approximately 20000 km (12428 mile) or yearly mileage of less than 2000 km (1243 mile)): Fuel quality (degradation, water contamination, etc.) For high mileage vehicles (ODO reading of more than approximately 150000 km (93210 mile)): Excessively lean air fuel ratio during acceleration due to deposits in intake system or combustion chamber caught temporarily on intake or exhaust valve or adherence of fuel to the deposits Abnormal mass air flow meter sub-assembly output due to existence of foreign matter Decrease in fuel injector assembly injection volume due to low quality fuel
Engine stalls or is difficult to start immediately after engine stalled, regardless of whether engine is cold or warm	Deposits in intake system or combustion chamber caught temporarily on intake or exhaust valve
When decelerating vehicle to a stop, engine speed drops momentarily and vehicle shudders When moving shift lever from N to D or R, or operating air conditioning system or any electrical components, engine speed fluctuates and vehicle shudders	Temporary deviation in the electrical throttle system idle speed control due to external factors (fuel quality, air conditioning system (environmental causes or low refrigerant pressure) or charging system (battery deterioration or low power generation by the alternator))

2.	CHECK DTC OUTPUT

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(d) Perform a road test.

(e) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

(f) Read the DTCs.

Powertrain > Engine and ECT > Trouble Codes

Result

Proceed to

DTCs are not output

DTC is output

(DTCs other than P1603, P1604 or P1605 are output)

GO TO DTC CHART

3.	SYMPTOM CONFIRMATION

(a) Check if the problem symptoms reported in the customer problem analysis recur.

HINT:

If the problem symptoms do not recur, attempt to reproduce the conditions when the malfunction occurred based on the result of the customer problem analysis.

Result	Proceed to
The problem symptom recurs	A
The problem symptom does not recur (occurred in the past)	B

CHECK FOR INTERMITTENT PROBLEMS

4.	READ VALUE USING TECHSTREAM (ISC LEARNING VALUE)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(d) Enter the following menus: Powertrain / Engine and ECT / Data List / ISC Learning Value.

Powertrain > Engine and ECT > Data List

Tester Display
ISC Learning Value

(e) Read the value displayed on the Techstream.

Result	Proceed to
Less than 6.2 L/s	A
Other than above	B

GO TO STEP 11

5.	READ VALUE USING TECHSTREAM (SHORT FT B1S1 AND LONG FT B1S1)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(d) Enter the following menus: Powertrain / Engine and ECT / Data List / Short FT B1S1 and Long FT B1S1.

Powertrain > Engine and ECT > Data List

Tester Display
Short FT B1S1
Long FT B1S1

(e) Read the value displayed on the Techstream.

Data List	Result	Proceed to
Short FT B1S1 + Long FT B1S1	-15% or higher, or less than 15%	A
Short FT B1S1 + Long FT B1S1	Other than above	B

HINT:

"Total FT #1" is used to detect an abnormal air fuel ratio. As the value of "Total FT #1" is corrected by the ECM before it is displayed in the Data List, the displayed value may not be equal to the sum of the measured "Short FT B1S1" and "Long FT B1S1".
An abnormally lean or rich tendency can be checked by reading the following Data List items: A/F Learn Value Idle #1, A/F Learn Value Low #1, A/F Learn Value Mid1 #1, A/F Learn Value Mid2 #1 and A/F Learn Value High #1.
The following may cause a lean air fuel ratio (an operating range in which the air fuel ratio learned value correction is +15% or more):
1. Decrease in fuel injector assembly injection volume
2. Decrease in mass air flow meter sub-assembly output (due to existence of foreign matter)
3. Air leaks in intake system after mass air flow meter sub-assembly
4. Decrease in fuel pressure (at fuel filter, fuel pump or fuel pressure regulator assembly)
On vehicles which the learning value for each operating range can be checked, if the value of "A/F Learn Value High #1" only is corrected to the positive side, a malfunction in the fuel system (clogging of the fuel pump or fuel filter) is suspected.
On vehicles which the learning value for each operating range can be checked, if the value of "A/F Learn Value Idle #1" or "A/F Learn Value Low #1" only is corrected to the positive side, an air leak after the mass air flow meter sub-assembly is suspected.
The following may cause a rich air fuel ratio (an operating range in which the air fuel ratio learned value correction is -15% or less):
1. Increase in the fuel injector assembly injection volume
2. Purge VSV system

GO TO STEP 15

6.	PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE SELECT CYLINDER FUEL CUT)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(d) Start the engine.

HINT:

Reproduce the vehicle conditions when the malfunction occurred. (such as after the engine is warmed up or after a cold start).

(e) Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Select Cylinder Fuel Cut / Data List / Engine Speed.

Powertrain > Engine and ECT > Active Test

Active Test Display
Control the Select Cylinder Fuel Cut

Data List Display
Engine Speed

(f) According to the display on the Techstream, perform the Active Test and check for a malfunctioning cylinder.

HINT:

Perform fuel-cut for each cylinder and check the change in the engine speed.
If the engine speed of a cylinder does not change while performing the Active Test, it can be determined that the cylinder is malfunctioning.
If the engine speed of all cylinders change while performing the Active Test, it can be determined that multiple cylinders are malfunctioning.
A cylinder for which the Data List item "Cylinder Misfire Count" increases may be malfunctioning.
If "Compression Leakage Count" in the Data List increases, misfiring due to insufficient compression may be occurring.

Result	Proceed to
One cylinder is malfunctioning	A
Multiple or all cylinders are malfunctioning, or the malfunctioning cylinder cannot be determined.	B

GO TO STEP 15

7.	PERFORM ACTIVE TEST USING TECHSTREAM (CHECK THE CYLINDER COMPRESSION)

HINT:

If the vehicle does not support the Active Test "Check the Cylinder Compression", measure the compression pressure. If the compression pressure is normal, go to step 8 (PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE INJECTION VOLUME)).

(a) Warm up the engine.

(b) Turn the ignition switch off.

(d) Turn the ignition switch to ON.

(e) Turn the Techstream on.

(f) Enter the following menus: Powertrain / Engine and ECT / Active Test / Check the Cylinder Compression / Data List / Compression / Engine Speed of Cyl #1 to #4 and Av Engine Speed of All Cyl.

Powertrain > Engine and ECT > Active Test

Active Test Display
Check the Cylinder Compression

Data List Display
Engine Speed of Cyl #1
Engine Speed of Cyl #2
Engine Speed of Cyl #3
Engine Speed of Cyl #4
Av Engine Speed of All Cyl

HINT:

To display the entire Data List, press the pull down menu button next to Primary. Then select Compression.

(g) Push the snapshot button to turn the snapshot function on.

HINT:

Using the snapshot function, data can be recorded during the Active Test.

(h) While the engine is not running, press the Active Test button to change Check the Cylinder Compression to ON.

HINT:

After performing the above procedure, the Active Test will start. Fuel injection for all cylinders is prohibited and each cylinder engine speed measurement enters standby mode.

(i) Crank the engine for about 10 seconds.

HINT:

Continue to crank the engine until the values change from the default value (51199 rpm).

(j) Monitor the engine speed (Engine Speed of Cyl #1 to #4 and Av Engine Speed of All Cyl) displayed on the Techstream.

NOTICE:

In order to protect the starter assembly, do not crank the engine continuously for 20 seconds or more.
If it is necessary to crank the engine again after Check the Cylinder Compression has been changed to ON and the engine has been cranked once, press Exit to return to the Active Test menu screen. Then change Check the Cylinder Compression to ON and crank the engine.
Make sure the battery is fully charged before performing this Active Test.

HINT:

At first, the Techstream will display extremely high cylinder engine speed values. After approximately 10 seconds of engine cranking, the engine speed measurement of each cylinder will change to the actual engine speed.
If the cylinder engine speed values (Engine Speed of Cyl #1 to #4) displayed in the Data List do not change from an extremely high value, return to the Active Test menu screen, change "Check the Cylinder Compression" to ON and crank the engine again within 1 second.

(k) Stop cranking the engine, and then change "Check the Cylinder Compression" to OFF after the engine stops.

NOTICE:

If the Active Test is changed to OFF while the engine is being cranked, the engine will start.
When performing the Active Test, DTC P1604 (Startability Malfunction) may be stored.
After performing the Active Test, make sure to check and clear DTCs.

(l) Push the snapshot button to turn the snapshot function off.

(m) Select "Stored Data" on the Techstream screen, select the recorded data and display the data as a graph.

HINT:

If the data is not displayed as a graph, the change of the values cannot be observed.

(n) Read the value.

HINT:

If the value of Data List item "Engine Speed of Cyl" of a cylinder is higher than other cylinders, the cylinder may be malfunctioning.
If the value of Data List item "Engine Speed of Cyl" is high for only one cylinder, compression loss is suspected.

Result

Proceed to

There is no variation in "Engine Speed of Cyl"

(All cylinders display approximately the same value for "Engine Speed of Cyl")

There is variation in "Engine Speed of Cyl"

(Only one cylinder displays a value for "Engine Speed of Cyl" that differs considerably)

GO TO STEP 13

8.	PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE INJECTION VOLUME)

(a) Connect the Techstream to the DLC3.

(b) Start the engine and warm it up until the engine coolant temperature 75°C (167°F) or higher with all the accessories switched off.

(d) Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume / Data List / Coolant Temp.

Powertrain > Engine and ECT > Active Test

Active Test Display
Control the Injection Volume

Data List Display
Coolant Temp

(e) According to the display on the Techstream, perform the Active Test and check the vehicle conditions when increasing and decreasing the fuel injection volume.

HINT:

Change the fuel injection volume between the minimum and maximum range of correction (e.g. -12.5% to 12.5%).

Result	Proceed to
Malfunction is still present even if the fuel injection volume is changed	A
Malfunction disappears when the fuel injection volume is changed	B

GO TO STEP 14

9.	CHECK IGNITION SYSTEM

(a) Check the ignition system.

HINT:

Interchange the ignition coil assembly and spark plug of the malfunctioning cylinder with those of a known good cylinder and check if the malfunctioning cylinder returns to normal.
If the spark plug of the malfunctioning cylinder is abnormally wet with fuel even after the ignition coil assembly and spark plug are replaced, a leaking fuel injector assembly is suspected.

Result	Proceed to
The malfunctioning cylinder does not return to normal	A
The malfunctioning cylinder returned to normal	B

GO TO STEP 21

10.	INSPECT OTHER RELATED COMPONENTS

(a) Check the power source circuit, wire harness and connectors.

GO TO STEP 21

11.	REMOVE FOREIGN OBJECT (CLEAN THROTTLE BODY ASSEMBLY)

(a) Clean off any deposits from the inside of the throttle body assembly.

(b) Push open the throttle valve and wipe off any carbon from the valve and bore using a piece of cloth soaked in non-residue solvent.

*1	Throttle Body Assembly	*2	Bore
*3	Valve	-	-
*a	Reference	*b	Throttle Body Assembly Cross-section Diagram
*c	When valve fully opened	*d	Do not directly apply cleaner
*e	Deposits	-	-

NOTICE:

Make sure that the cloth or your fingers do not get caught in the valve.
Make sure that foreign matter does not enter the throttle valve.
Do not directly apply non-residue solvent to the throttle body assembly or wash the throttle body assembly. Cleaning solvent may leak into the motor from the shaft and cause problems such as rust or valve movement problems.
If there is coating material on the edge of the valve, be careful not to remove it.

HINT:

The illustrations are for reference only. Actual parts may differ.

12.	PERFORM CONFIRMATION DRIVING PATTERN

(a) Perform "Inspection After Repair" after cleaning the throttle body assembly.

Click here

(b) Connect the Techstream to the DLC3.

(d) Turn the Techstream on.

(e) Allow the engine to idle for 3 minutes or more and confirm that the engine speed is within the specified range.

HINT:

If the engine is operated without performing learning value reset and idle learning after cleaning the deposits from the throttle body assembly, the idle speed may increase.

GO TO STEP 22

13.	CHECK CYLINDER COMPRESSION PRESSURE

(a) Measure the cylinder compression pressure. If the compression pressure of a cylinder is low, inspect the engine assembly and repair or replace parts as necessary.

Click here

GO TO STEP 21

14.	REPLACE FUEL INJECTOR ASSEMBLY

(a) Replace the fuel injector assembly of the malfunctioning cylinder.

Click here

HINT:

If the air fuel ratio learned value is corrected to the positive side for all operating ranges due to low fuel injector assembly injection volume, replace the fuel injector assemblies of all cylinders.
Perform "Inspection After Repair" after replacing the fuel injector assembly.
Click here

GO TO STEP 22

15.	READ VALUE USING TECHSTREAM (MAF)

(a) Connect the Techstream to the DLC3.

(b) Start the engine and warm it up until the engine coolant temperature 75°C (167°F) or higher with all the accessories switched off.

(d) Enter the following menus: Powertrain / Engine and ECT / Data List / Engine Speed, MAF and Coolant Temp.

Powertrain > Engine and ECT > Data List

Tester Display
Engine Speed
MAF
Coolant Temp

(e) According to the display on the Techstream, read the Data List when the engine is running.

Result	Proceed to
Idling (engine warmed up): 1.0 to 3.0 gm/sec Engine speed 3000 rpm (without load): 5.0 to 10.0 gm/sec	A
Other than above	B

GO TO STEP 19

16.	PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE INJECTION VOLUME FOR A/F SENSOR)

(a) Connect the Techstream to the DLC3.

(b) Start the engine and warm it up until the engine coolant temperature 75°C (167°F) or higher with all the accessories switched off.

(d) Warm up the air fuel ratio sensor at an engine speed of 2500 rpm for 90 seconds.

(e) Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume for A/F Sensor / Data List / Coolant Temp, AFS Voltage B1S1 and O2S B1S2.

Powertrain > Engine and ECT > Active Test

Active Test Display
Control the Injection Volume for A/F Sensor

Data List Display
Coolant Temp
AFS Voltage B1S1
O2S B1S2

(f) According to the display on the Techstream, perform the Active Test and check the vehicle conditions when increasing and decreasing the fuel injection volume.

NOTICE:

The air fuel ratio sensor has an output delay of a few seconds and the heated oxygen sensor has a maximum output delay of approximately 20 seconds.
Read the output voltage immediately after warming up the air fuel ratio sensor and heated oxygen sensor to avoid an inaccurate reading due to a sensor cooling.

HINT:

The Control the Injection Volume for A/F Sensor operation lowers the fuel injection volume by 12.5% or increases the injection volume by 12.5%.

Techstream Display (Sensor)	Injection Volume	Voltage
AFS Voltage B1S1 (Air fuel ratio)	12.5%	Below 3.1 V
AFS Voltage B1S1 (Air fuel ratio)	-12.5%	Higher than 3.4 V
O2S B1S2 (Heated oxygen)	12.5%	Higher than 0.55 V
O2S B1S2 (Heated oxygen)	-12.5%	Below 0.4 V

Result	Proceed to
Output voltage values are abnormal	A
Malfunction disappears when fuel injection volume is increased	B
Malfunction is still present when fuel injection volume is increased, even if output voltage values are normal	C

GO TO STEP 18

GO TO STEP 20

17.	REPLACE AIR FUEL RATIO SENSOR AND HEATED OXYGEN SENSOR

(a) Replace the air fuel ratio sensor.

Click here

HINT:

Perform "Inspection After Repair" after replacing the air fuel ratio sensor.

Click here

(b) Replace the heated oxygen sensor.

Click here

HINT:

Perform "Inspection After Repair" after replacing the heated oxygen sensor.

Click here

GO TO STEP 22

18.	REPLACE FUEL INJECTOR ASSEMBLY

(a) Replace the fuel injector assemblies of all cylinders.

Click here

HINT:

Perform "Inspection After Repair" after replacing the fuel injector assembly.

Click here

GO TO STEP 22

19.	CHECK INTAKE SYSTEM

(a) Check for air leaks or blockage in the intake system components. If a connection problem or foreign matter is found, repair the connection or remove the foreign matter.

HINT:

If there is foreign matter in the intake system components, remove it before proceeding to the next step.
If there is no foreign matter in the intake system components, check for foreign matter in the mass air flow meter sub-assembly. If there is foreign matter in the mass air flow meter sub-assembly, remove it.

GO TO STEP 21

20.	INSPECT OTHER RELATED COMPONENTS

(a) Inspect other related components.

HINT:

If the malfunctioning part could not be determined by performing the preceding inspections, one of the following malfunctions is suspected.

Engine mount deterioration
Deposits in the intake manifold or on an intake valve
Delay in fuel supply due to adherence of the fuel to the deposits

21.	REPAIR OR REPLACE MALFUNCTIONING PARTS

(a) Repair or replace the malfunctioning part.

HINT:

Perform "Inspection After Repair" after repairing or replacing the malfunctioning part.

Click here

22.	CONDUCT CONFIRMATION TEST

(a) Check that the idle has returned to normal.

END