LOW IDLE/STALLS DURING DECELERATION [SKYACTIV-D]

Troubleshooting item	LOW IDLE/STALLS DURING DECELERATION
Description	• Engine speed decreases when the accelerator pedal is released. • Stalls during deceleration with the accelerator pedal fully released. • When the accelerator pedal is fully released, vehicle stalls directly after vehicle stops.
Possible cause	• PCM DTC is stored. • A/C relay malfunction • ECT sensor malfunction • Fuel injection system malfunction ― Fuel leakage from fuel system ― Common rail malfunction ― Supply pump malfunction ― Suction control valve malfunction ― Fuel injector malfunction ― Fuel pressure relief valve malfunction • Intake shutter valve malfunction ― Intake shutter valve blockage • Poor fuel quality • Mechanical (engine) malfunction ― Large mechanical resistance (such as A/C compressor) ― Improper engine compression ― Improper valve timing ― Engine oil malfunction (oil working up or down) • ATX malfunction (ATX) Warning • The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before performing the fuel system services: ― Always keep sparks and flames away from fuel. Fuel can be easily ignited which could cause serious injury or death, and damage to equipment. ― Fuel line spills and leakage from the pressurized fuel system are dangerous. Fuel can ignite and cause serious injury or death, and damage to property and facilities. Fuel can also irritate skin and eyes. To prevent this, always complete the "Fuel Line Safety Procedure", while referring to the "BEFORE SERVICE PRECAUTION". (See BEFORE SERVICE PRECAUTION [SKYACTIV-D 1.8].) ― Fuel is highly flammable and dangerous. Fuel line spills and leakage can cause serious injury or death, and damage to equipment. When installing the fuel hose, always refer to the "AFTER SERVICE PRECAUTION" and perform the "Fuel Hose Installation Procedure". (See AFTER SERVICE PRECAUTION [SKYACTIV-D 1.8].)
System wiring diagram	• Not applicable
Connector diagram	• Not applicable

Troubleshooting item

LOW IDLE/STALLS DURING DECELERATION

Description

• Engine speed decreases when the accelerator pedal is released.

• Stalls during deceleration with the accelerator pedal fully released.

• When the accelerator pedal is fully released, vehicle stalls directly after vehicle stops.

Possible cause

• PCM DTC is stored.

• A/C relay malfunction

• ECT sensor malfunction

• Fuel injection system malfunction

― Fuel leakage from fuel system

― Common rail malfunction

― Supply pump malfunction

― Suction control valve malfunction

― Fuel injector malfunction

― Fuel pressure relief valve malfunction

• Intake shutter valve malfunction

― Intake shutter valve blockage

• Poor fuel quality

• Mechanical (engine) malfunction

― Large mechanical resistance (such as A/C compressor)

― Improper engine compression

― Improper valve timing

― Engine oil malfunction (oil working up or down)

• ATX malfunction (ATX)

Warning

• The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before performing the fuel system services:

― Always keep sparks and flames away from fuel. Fuel can be easily ignited which could cause serious injury or death, and damage to equipment.

― Fuel line spills and leakage from the pressurized fuel system are dangerous. Fuel can ignite and cause serious injury or death, and damage to property and facilities. Fuel can also irritate skin and eyes. To prevent this, always complete the "Fuel Line Safety Procedure", while referring to the "BEFORE SERVICE PRECAUTION". (See BEFORE SERVICE PRECAUTION [SKYACTIV-D 1.8].)

― Fuel is highly flammable and dangerous. Fuel line spills and leakage can cause serious injury or death, and damage to equipment. When installing the fuel hose, always refer to the "AFTER SERVICE PRECAUTION" and perform the "Fuel Hose Installation Procedure". (See AFTER SERVICE PRECAUTION [SKYACTIV-D 1.8].)

System wiring diagram

• Not applicable

Connector diagram

• Not applicable

Step	Inspection	Results	Action
1	VERIFY PCM DTC • Retrieve PCM DTCs using the M-MDS. (See DTC INSPECTION.) • Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [PCM (SKYACTIV-D)].)
No	Go to the next step.
2	INSPECT A/C RELAY • Switch the ignition off. • Remove the A/C relay. • Inspect the A/C relay. (See RELAY INSPECTION.) • Is the A/C relay normal?	Yes	Go to the next step.
No	Replace the A/C relay, then go to repair completion verification.
3	INSPECT ECT SENSOR • Inspect the ECT sensor. (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION [SKYACTIV-D 1.8].) • Is the ECT sensor normal?	Yes	Go to the next step.
No	Replace the ECT sensor, then go to repair completion verification. (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)
4	INSPECT FOR FUEL LEAKAGE FROM FUEL SYSTEM • Visually inspect the following: ― Fuel leakage from the fuel tank, fuel pump, hose, pipe, fuel injector, supply pump, common rail ― Cracking and damage in fuel hose and pipe ― Clamp installation condition for each hose and pipe ― Fuel pipe securing condition due to deterioration such as rubber of clamp • Are all items normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning part according to the inspection results, then go to repair completion verification.
5	INSPECT FUEL INJECTION RELATED PARTS • Inspect the following parts: ― Common rail (See COMMON RAIL INSPECTION [SKYACTIV-D 1.8].) ― Supply pump (See SUPPLY PUMP INSPECTION [SKYACTIV-D 1.8].) ― Suction control valve (See SUCTION CONTROL VALVE INSPECTION [SKYACTIV-D 1.8].) ― Fuel injector (See FUEL INJECTOR INSPECTION [SKYACTIV-D 1.8].) ― Fuel pressure relief valve (See FUEL PRESSURE RELIEF VALVE INSPECTION [SKYACTIV-D 1.8].) • Are all items normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning part according to the inspection results, then go to repair completion verification.
6	INSPECT FOR MALFUNCTION DUE TO POOR FUEL • Replace the fuel. (See FUEL DRAINING PROCEDURE [SKYACTIV-D 1.8].) • Does the symptom disappear?	Yes	Advise the customer as to the change in the fuel used.
No	Remove the accumulated matter in the cylinder head using the following procedure, then go to the next step. • Carbon remover • Overhauling
7	DETERMINE IF MALFUNCTION IS DUE TO EXCESSIVE ENGINE SPEED RESISTANCE • Rotate the crankshaft pulley lock bolt clockwise using a wrench. (See FRONT OIL SEAL REPLACEMENT [SKYACTIV-D 1.8].) • Can bolts be rotated?	Yes	ATX: • Go to Step 9. MTX: • Go to Step 10.
No	Go to the next step.
8	INSPECT FOR MALFUNCTION DUE TO EXCESSIVE MECHANICAL RESISTANCE OF ENGINE ACCESSORIES • Remove all drive belts from engine accessories. (See DRIVE BELT REMOVAL/INSTALLATION [SKYACTIV-D 1.8].) Caution • Do not run the engine for long periods with the drive belts of engine accessories removed. Otherwise the engine could be damaged from overheating. • Start the engine. • Is cranking possible? (Does the engine start?)	Yes	Repair or replace the malfunctioning part according to the inspection results, then go to repair completion verification. (Large mechanical resistance in engine accessories such as the A/C compressor.)
No	ATX: • Go to the next step. MTX: • Go to Step 10.
9	VERIFY ATX DTC • Retrieve any DTCs using the M-MDS. (See DTC INSPECTION.) • Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See ON-BOARD DIAGNOSTIC SYSTEM DTC TABLE [TCM (ET6A-EL, ET6AX-EL) (E)].)
No	Go to the next step.
10	INSPECT ENGINE COMPRESSION • Inspect the engine compression. (See COMPRESSION INSPECTION [SKYACTIV-D 1.8].) • Are compression pressures within specification?	Yes	Go to repair completion verification.
No	Go to the next step.
11	INSPECT FOR MALFUNCTION DUE TO DEVIATED VALVE TIMING • Inspect the valve timing (timing chain installation condition). (See TIMING CHAIN REMOVAL/INSTALLATION [SKYACTIV-D 1.8].) • Is the valve timing normal?	Yes	Inspect for the following engine internal parts: • Cylinder • Piston ring • Intake valve • Exhaust valve • Such as cylinder head gasket Repair or replace the malfunctioning part according to the inspection results, then go to the next step.
No	Adjust the valve timing to the correct timing, then go to the next step.
Repair completion verification 1	VERIFY THAT VEHICLE IS REPAIRED • Install/connect the part removed/disconnected during the troubleshooting procedure. • Has the malfunction symptom been eliminated?	Yes	Complete the symptom troubleshooting. (Explain contents of repair to customer)
No	Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].) • If the CAN communication is normal, perform the diagnosis from Step 1. ― If the malfunction recurs, go to the next step.
Repair completion verification 2	VERIFY IF MALFUNCTION IS CAUSED BY NOT PERFORMING PCM REPROGRAMMING • Verify repair information and verify that there is a new calibration in the PCM. • Is there a new calibration in the PCM?	Yes	Perform the PCM reprogramming and verify if the malfunction symptom was corrected. • If the malfunction recurs, replace the PCM. (See PCM REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)
No	Replace the PCM. (See PCM REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)

Step

Inspection

Results

Action

VERIFY PCM DTC

• Retrieve PCM DTCs using the M-MDS.

(See DTC INSPECTION.)

• Are any DTCs present?

Yes

Go to the applicable DTC inspection.

(See DTC TABLE [PCM (SKYACTIV-D)].)

Go to the next step.

INSPECT A/C RELAY

• Switch the ignition off.

• Remove the A/C relay.

• Inspect the A/C relay.

(See RELAY INSPECTION.)

• Is the A/C relay normal?

Yes

Go to the next step.

Replace the A/C relay, then go to repair completion verification.

INSPECT ECT SENSOR

• Inspect the ECT sensor.

(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION [SKYACTIV-D 1.8].)

• Is the ECT sensor normal?

Yes

Go to the next step.

Replace the ECT sensor, then go to repair completion verification.

(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)

INSPECT FOR FUEL LEAKAGE FROM FUEL SYSTEM

• Visually inspect the following:

― Fuel leakage from the fuel tank, fuel pump, hose, pipe, fuel injector, supply pump, common rail

― Cracking and damage in fuel hose and pipe

― Clamp installation condition for each hose and pipe

― Fuel pipe securing condition due to deterioration such as rubber of clamp

• Are all items normal?

Yes

Go to the next step.

Repair or replace the malfunctioning part according to the inspection results, then go to repair completion verification.

INSPECT FUEL INJECTION RELATED PARTS

• Inspect the following parts:

― Common rail

(See COMMON RAIL INSPECTION [SKYACTIV-D 1.8].)

― Supply pump

(See SUPPLY PUMP INSPECTION [SKYACTIV-D 1.8].)

― Suction control valve

(See SUCTION CONTROL VALVE INSPECTION [SKYACTIV-D 1.8].)

― Fuel injector

(See FUEL INJECTOR INSPECTION [SKYACTIV-D 1.8].)

― Fuel pressure relief valve

(See FUEL PRESSURE RELIEF VALVE INSPECTION [SKYACTIV-D 1.8].)

• Are all items normal?

Yes

Go to the next step.

Repair or replace the malfunctioning part according to the inspection results, then go to repair completion verification.

INSPECT FOR MALFUNCTION DUE TO POOR FUEL

• Replace the fuel.

(See FUEL DRAINING PROCEDURE [SKYACTIV-D 1.8].)

• Does the symptom disappear?

Yes

Advise the customer as to the change in the fuel used.

Remove the accumulated matter in the cylinder head using the following procedure, then go to the next step.

• Carbon remover

• Overhauling

DETERMINE IF MALFUNCTION IS DUE TO EXCESSIVE ENGINE SPEED RESISTANCE

• Rotate the crankshaft pulley lock bolt clockwise using a wrench.

(See FRONT OIL SEAL REPLACEMENT [SKYACTIV-D 1.8].)

• Can bolts be rotated?

Yes

ATX:

• Go to Step 9.

MTX:

• Go to Step 10.

Go to the next step.

INSPECT FOR MALFUNCTION DUE TO EXCESSIVE MECHANICAL RESISTANCE OF ENGINE ACCESSORIES

• Remove all drive belts from engine accessories.

(See DRIVE BELT REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)

Caution

• Do not run the engine for long periods with the drive belts of engine accessories removed. Otherwise the engine could be damaged from overheating.

• Start the engine.

• Is cranking possible? (Does the engine start?)

Yes

Repair or replace the malfunctioning part according to the inspection results, then go to repair completion verification. (Large mechanical resistance in engine accessories such as the A/C compressor.)

ATX:

• Go to the next step.

MTX:

• Go to Step 10.

VERIFY ATX DTC

• Retrieve any DTCs using the M-MDS.

(See DTC INSPECTION.)

• Are any DTCs present?

Yes

Go to the applicable DTC inspection.

(See ON-BOARD DIAGNOSTIC SYSTEM DTC TABLE [TCM (ET6A-EL, ET6AX-EL) (E)].)

Go to the next step.

INSPECT ENGINE COMPRESSION

• Inspect the engine compression.

(See COMPRESSION INSPECTION [SKYACTIV-D 1.8].)

• Are compression pressures within specification?

Yes

Go to repair completion verification.

Go to the next step.

INSPECT FOR MALFUNCTION DUE TO DEVIATED VALVE TIMING

• Inspect the valve timing (timing chain installation condition).

(See TIMING CHAIN REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)

• Is the valve timing normal?

Yes

Inspect for the following engine internal parts:

• Cylinder

• Piston ring

• Intake valve

• Exhaust valve

• Such as cylinder head gasket

Repair or replace the malfunctioning part according to the inspection results, then go to the next step.

Adjust the valve timing to the correct timing, then go to the next step.

Repair completion verification 1

VERIFY THAT VEHICLE IS REPAIRED

• Install/connect the part removed/disconnected during the troubleshooting procedure.

• Has the malfunction symptom been eliminated?

Yes

Complete the symptom troubleshooting. (Explain contents of repair to customer)

Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.

(See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].)

• If the CAN communication is normal, perform the diagnosis from Step 1.

― If the malfunction recurs, go to the next step.

Repair completion verification 2

VERIFY IF MALFUNCTION IS CAUSED BY NOT PERFORMING PCM REPROGRAMMING

• Verify repair information and verify that there is a new calibration in the PCM.

• Is there a new calibration in the PCM?

Yes

Perform the PCM reprogramming and verify if the malfunction symptom was corrected.

• If the malfunction recurs, replace the PCM.

(See PCM REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)

Replace the PCM.

(See PCM REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)

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