NO.12 LACK/LOSS OF POWER-ACCELERATION/CRUISE [L3 Turbo]

12	LACK/LOSS OF POWER—ACCELERATION/CRUISE
DESCRIPTION	• Performance is poor under load (e.g., power down when climbing hills).
POSSIBLE CAUSE	• Drive-by-wire control system operates with brake override system (From BL**-198281,BL1*-239890) • Improper operation of A/C system • Improper operation of A/C cut-off control • Air leakage or restriction from intake-air system • Loose turbocharger compressor to intake manifold duct connecting • Turbocharger rotating assembly binding or dragging • Wastegate control solenoid valve malfunction (stuck open) • Turbocharger malfunction • Charge air cooler malfunction • Variable swirl system malfunction • Improper operation of electronic throttle control system • Purge solenoid valve malfunction • EGR system malfunction • Brake dragging • Low engine compression • Poor fuel quality • Vacuum leakage • Incorrect signal to ignition coil • Spark plug malfunction • Engine overheating • Throttle body malfunction • Air cleaner restriction or dirty • PCV valve malfunction • Improper valve timing due to jumping out of timing chain • Improper operation of variable valve timing control system • Restriction in exhaust system or TWC • Leakage at exhaust manifold or turbocharger mounting flange • Intermittent open or short fuel pump related circuit • Inadequate fuel pressure (high-or low pressure side) • Fuel pressure sensor (built-in fuel delivery pipe) malfunction • Spill valve control solenoid valve malfunction (built-in high pressure fuel pump) • Relief valve malfunction (built-in fuel delivery pipe) • High pressure fuel pump malfunction • Improper operation of fuel pump speed control • Fuel pump mechanical malfunction • Fuel line restriction or clogging • Fuel injector malfunction • Incorrect fuel injection timing • Erratic signal from CKP sensor • Erratic or no signal from CMP sensor • ECT sensor or related circuit malfunction • MAP sensor (integrated in MAP sensor/boost air temperature sensor) or related circuit malfunction • APP sensor or related circuit malfunction • MAF/IAT sensor or related circuit malfunction • Boost air temperature sensor (integrated in MAP sensor/boost air temperature sensor) or related circuit malfunction • Intermittent open or short circuit MAF sensor, APP sensor, TP sensor and VSS • Clutch slippage Warning • The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before performing the fuel system services: ― Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. ― Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injury or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete “BEFORE SERVICE PRECAUTION” and “AFTER SERVICE PRECAUTION” described in this manual. (See BEFORE SERVICE PRECAUTION [L3 Turbo].) (See AFTER SERVICE PRECAUTION [L3 Turbo].) Caution • Disconnecting/connecting the quick release connector without cleaning it may possibly cause damage to the fuel pipe and quick release connector. Always clean the quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.

LACK/LOSS OF POWER—ACCELERATION/CRUISE

DESCRIPTION

• Performance is poor under load (e.g., power down when climbing hills).

POSSIBLE CAUSE

• Drive-by-wire control system operates with brake override system (From BL****-198281,BL1***-239890)

• Improper operation of A/C system

• Improper operation of A/C cut-off control

• Air leakage or restriction from intake-air system

• Loose turbocharger compressor to intake manifold duct connecting

• Turbocharger rotating assembly binding or dragging

• Wastegate control solenoid valve malfunction (stuck open)

• Turbocharger malfunction

• Charge air cooler malfunction

• Variable swirl system malfunction

• Improper operation of electronic throttle control system

• Purge solenoid valve malfunction

• EGR system malfunction

• Brake dragging

• Low engine compression

• Poor fuel quality

• Vacuum leakage

• Incorrect signal to ignition coil

• Spark plug malfunction

• Engine overheating

• Throttle body malfunction

• Air cleaner restriction or dirty

• PCV valve malfunction

• Improper valve timing due to jumping out of timing chain

• Improper operation of variable valve timing control system

• Restriction in exhaust system or TWC

• Leakage at exhaust manifold or turbocharger mounting flange

• Intermittent open or short fuel pump related circuit

• Inadequate fuel pressure (high-or low pressure side)

• Fuel pressure sensor (built-in fuel delivery pipe) malfunction

• Spill valve control solenoid valve malfunction (built-in high pressure fuel pump)

• Relief valve malfunction (built-in fuel delivery pipe)

• High pressure fuel pump malfunction

• Improper operation of fuel pump speed control

• Fuel pump mechanical malfunction

• Fuel line restriction or clogging

• Fuel injector malfunction

• Incorrect fuel injection timing

• Erratic signal from CKP sensor

• Erratic or no signal from CMP sensor

• ECT sensor or related circuit malfunction

• MAP sensor (integrated in MAP sensor/boost air temperature sensor) or related circuit malfunction

• APP sensor or related circuit malfunction

• MAF/IAT sensor or related circuit malfunction

• Boost air temperature sensor (integrated in MAP sensor/boost air temperature sensor) or related circuit malfunction

• Intermittent open or short circuit MAF sensor, APP sensor, TP sensor and VSS

• Clutch slippage

Warning

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

― Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel.

― Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injury or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete “BEFORE SERVICE PRECAUTION” and “AFTER SERVICE PRECAUTION” described in this manual. (See BEFORE SERVICE PRECAUTION [L3 Turbo].) (See AFTER SERVICE PRECAUTION [L3 Turbo].)

Caution

• Disconnecting/connecting the quick release connector without cleaning it may possibly cause damage to the fuel pipe and quick release connector. Always clean the quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.

STEP	INSPECTION	RESULTS	ACTION
1^*1	CONFIRM DRIVE-BY-WIRE CONTROL SYSTEM OPERATES WITH BRAKE OVERRIDE SYSTEM • Retrieve the PCM DTC using the M-MDS. (See DTC P2299:00 [L3 Turbo]) • Is the DTC P2299 present?	Yes	Go to the applicable DTC inspection. (drive-by-wire control system operates with brake override system.) (See DTC P2299:00 [L3 Turbo])
No	Go to the next step.
2	Inspect for the following: • Fuel quality (proper octane, contamination, winter/summer blend) • Air cleaner restriction or dirty • Intake-air system restriction or leakage • Charge air cooler condition (restriction or damaged) • Turbocharger compressor-to-intake manifold duct loose connection • Leakage at exhaust manifold or turbocharger mounting flange • Vacuum leakage • Brake dragging • Clutch slippage Is there any malfunction?	Yes	Service if necessary. • Repeat this step.
No	Go to the next step.
3	Switch the ignition to ON. Retrieve any DTCs using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [L3 Turbo].) Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [L3 Turbo].)
No	Go to the next step.
4	Is the engine overheating?	Yes	Perform the symptom troubleshooting “NO.17 COOLING SYSTEM CONCERNS-OVERHEATING”. (See NO.17 COOLING SYSTEM CONCERNS-OVERHEATING [L3 Turbo].)
No	Go to the next step.
5	Perform the EGR Control System Inspection. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L3 Turbo].) Does the EGR system operate properly?	Yes	Go to the next step.
No	Repair or replace the malfunctioning parts according to the inspection results.
6	Perform the A/C Cut-off Control System Inspection. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L3 Turbo].) Does the A/C cut-off operation work properly?	Yes	Go to the next step.
No	Repair or replace the malfunctioning parts according to the inspection results.
7	Perform the TP sweep inspection. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L3 Turbo].) Does the electronic throttle control system work properly?	Yes	Visually inspect the throttle body (damage/scratching). • If normal: ― Go to the next step. • If not: ― Repair or replace the malfunctioning parts according to the inspection results.
No	Repair or replace the malfunctioning parts according to the inspection results.
8	Perform the Variable Swirl System Operation Inspection. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L3 Turbo].) Does the variable swirl system work properly?	Yes	Go to the next step.
No	Repair or replace the malfunctioning parts according to the inspection results.
9	Perform the Variable Valve Timing Control System Operation Inspection. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L3 Turbo].) Does the variable valve timing control system work properly?	Yes	Go to the next step.
No	Repair or replace the malfunctioning parts according to the inspection results.
10	Perform the Purge Control System Inspection. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L3 Turbo].) Does the purge solenoid valve work properly?	Yes	Go to the next step.
No	Repair or replace the malfunctioning parts according to the inspection results.
11	Perform the Fuel Pump Speed Control Inspection. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L3 Turbo].) Does the fuel pump speed control work properly?	Yes	Go to the next step.
No	Repair or replace the malfunctioning parts according to the inspection results.
12	Perform the Wastegate Control System Operation Inspection. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L3 Turbo].) Does the wastegate control system work properly?	Yes	Go to the next step.
No	Repair or replace the malfunctioning parts according to the inspection results.
13	Access the following PIDs using the M-MDS: (See ON-BOARD DIAGNOSTIC TEST [L3 Turbo].) • BAT • ECT • MAF • IAT • APP1 • APP2 • TP REL • MAP • FP (Low side pressure line) • VSS Do the PID values indicate the correct values under the trouble condition? (See PCM INSPECTION [L3 Turbo].)	Yes	Go to the next step.
No	Inspect the suspected parts and related wiring harness. • If normal: ― Perform the “INTERMITTENT CONCERN TROUBLESHOOTING. (See INTERMITTENT CONCERN TROUBLESHOOTING [L3 Turbo].) • If not: ― Repair or replace the malfunctioning parts according to the inspection results.
14	Inspect the CMP sensor and CKP sensor for the following: • Installation condition (See CAMSHAFT POSITION (CMP) SENSOR REMOVAL/INSTALLATION [L3 Turbo].) (See CRANKSHAFT POSITION (CKP) SENSOR REMOVAL/INSTALLATION [L3 Turbo].) • Damaged trigger wheel and camshaft • Open or short circuit in the wiring harnesses Is there any malfunction?	Yes	Repair or replace the malfunctioning parts according to the inspection results.
No	Go to the next step.
15	Inspect the spark plug condition. Is the spark plug wet, covered with carbon or grayish white?	Yes	Spark plug is wet or covered with carbon: • Perform the Spark Test. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L3 Turbo].) • Repair or replace the malfunctioning parts according to the inspection results. Spark plug is grayish white: • Go to Step 25.
No	Reinstall the spark plugs on the original cylinders, then go to the next step.
16	Inspect for restriction in the exhaust system and TWC. Is there any restriction?	Yes	Repair or replace the malfunctioning parts according to the inspection results.
No	Go to the next step.
17	Remove the parts necessary to inspect the turbocharger without removing the turbocharger. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3 Turbo].) Inspect if the turbocharger compressor wheel is bent, damaged, or interfering with housing on vehicle. (See TURBOCHARGER INSPECTION [L3 Turbo].) Is there any malfunction?	Yes	Replace the turbocharger. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3 Turbo].)
No	Go to the next step.
18	Inspect the turbocharger compressor wheel locknut is loose or has fallen down inside the turbocharger. Is there any malfunction?	Yes	Replace the turbocharger. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3 Turbo].)
No	Go to the next step.
19	Inspect the turbocharger compressor wheel by hand. Does the wheel turn easily and smoothly?	Yes	Go to the next step.
No	Replace the turbocharger. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3 Turbo].)
20	Inspect the turbocharger turbine wheel is damaged, cracked or interfering with housing on vehicle. Note • Inspect all fins on each turbine wheel. Is there any malfunction?	Yes	Replace the turbocharger. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3 Turbo].)
No	Go to the next step.
21	Is any engine oil found inside the turbocharger turbine housing?	Yes	Excessive amount of oil is found: • Replace the turbocharger. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3 Turbo].) Small amount of oil is found: • Wipe the oil out of the vehicle, then go to the next step.
No	Go to the next step.
22	Is any engine oil found inside the turbocharger compressor housing?	Yes	Wipe the oil out of the vehicle and install all removed parts in Step 17, then go to the next step.
No	Turbocharger is normal: • Install all removed parts in Step 17, then go to the next step.
23	Inspect for fuel leakage in the fuel line. Is there any leakage?	Yes	Repair or replace the malfunctioning parts according to the inspection results.
No	Go to the next step.
24	Access the FUEL_PRES PID using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [L3 Turbo].) Is the FUEL_PRES PID value within the specification? (See PCM INSPECTION [L3 Turbo].)	Yes	Go to Step 28.
No	Go to the next step.
25	Replace the high pressure fuel pump. (See HIGH PRESSURE FUEL PUMP REMOVAL/INSTALLATION [L3 Turbo].) Access the FUEL_PRES PID using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [L3 Turbo].) Is the FUEL_PRES PID value within the specified? (See PCM INSPECTION [L3 Turbo].)	Yes	High-pressure fuel pump or spill valve control solenoid valve (built-in high pressure fuel pump) malfunction.
No	Relief valve or fuel pressure sensor malfunction. • Replace the fuel delivery pipe. (See FUEL INJECTOR REMOVAL/INSTALLATION [L3 Turbo].)
26	Connect the fuel pressure gauge between the fuel pump and the high pressure fuel pump. Measure the fuel pressure line of the low pressure side. (See FUEL LINE PRESSURE INSPECTION [L3 Turbo].) Is the fuel pressure within the specification?	Yes	Go to the next step.
No	Inspect for the following: • Fuel line restriction • Fuel filter clogging • If normal: ― Replace the fuel pump unit. (See FUEL PUMP UNIT REMOVAL/INSTALLATION [L3 Turbo].) • If not: ― Repair or replace the malfunctioning parts according to the inspection results.
27	Perform the Fuel Injector Operation Inspection. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L3 Turbo].) Do the fuel injectors operate normally?	Yes	Go to the next step.
No	Repair or replace the malfunctioning parts according to the inspection results.
28	Measure the compression pressure for each cylinder. (See COMPRESSION INSPECTION [L3 Turbo].) Are compression pressures within the specification?	Yes	Go to the next step.
No	Inspect for the following: • Damaged valve seat • Worn valve stem and valve guide • Worn or stuck piston ring • Worn piston, piston ring or cylinder • Improper valve timing Repair or replace the malfunctioning parts according to the inspection results.
29	Inspect the PCV valve. (See POSITIVE CRANKCASE VENTILATION (PCV) VALVE INSPECTION [L3 Turbo].) Is there any malfunction?	Yes	Replace the PCV valve. (See POSITIVE CRANKCASE VENTILATION (PCV) VALVE REMOVAL/INSTALLATION [L3 Turbo].)
No	Replace the PCM (injector driver circuit malfunction). (See PCM REMOVAL/INSTALLATION [L3 Turbo].) • If a malfunction remains: ― Repair or replace the malfunctioning part according to the inspection results.
30	Verify test results. • If normal, return to the diagnostic index to service any additional symptoms. • If a malfunction remains, inspect the related Service Information and perform the repair or diagnosis. ― If the vehicle is repaired, troubleshooting is completed. ― If the vehicle is not repaired or additional diagnostic information is not available, reprogram the PCM if a later calibration is available. Retest.

STEP

INSPECTION

RESULTS

ACTION

1^*1

CONFIRM DRIVE-BY-WIRE CONTROL SYSTEM OPERATES WITH BRAKE OVERRIDE SYSTEM

• Retrieve the PCM DTC using the M-MDS.

(See DTC P2299:00 [L3 Turbo])

• Is the DTC P2299 present?

Yes

Go to the applicable DTC inspection. (drive-by-wire control system operates with brake override system.)

(See DTC P2299:00 [L3 Turbo])

Go to the next step.

Inspect for the following:

• Fuel quality (proper octane, contamination, winter/summer blend)

• Air cleaner restriction or dirty

• Intake-air system restriction or leakage

• Charge air cooler condition (restriction or damaged)

• Turbocharger compressor-to-intake manifold duct loose connection

• Leakage at exhaust manifold or turbocharger mounting flange

• Vacuum leakage

• Brake dragging

• Clutch slippage

Is there any malfunction?

Yes

Service if necessary.

• Repeat this step.

Go to the next step.

Switch the ignition to ON.

Retrieve any DTCs using the M-MDS.

(See ON-BOARD DIAGNOSTIC TEST [L3 Turbo].)

Are any DTCs present?

Yes

Go to the applicable DTC inspection.

(See DTC TABLE [L3 Turbo].)

Go to the next step.

Is the engine overheating?

Yes

Perform the symptom troubleshooting “NO.17 COOLING SYSTEM CONCERNS-OVERHEATING”.

(See NO.17 COOLING SYSTEM CONCERNS-OVERHEATING [L3 Turbo].)

Go to the next step.

Perform the EGR Control System Inspection.

(See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L3 Turbo].)

Does the EGR system operate properly?

Yes

Go to the next step.

Repair or replace the malfunctioning parts according to the inspection results.

Perform the A/C Cut-off Control System Inspection.

(See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L3 Turbo].)

Does the A/C cut-off operation work properly?

Yes

Go to the next step.

Repair or replace the malfunctioning parts according to the inspection results.

Perform the TP sweep inspection.

(See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L3 Turbo].)

Does the electronic throttle control system work properly?

Yes

Visually inspect the throttle body (damage/scratching).

• If normal:

― Go to the next step.

• If not:

― Repair or replace the malfunctioning parts according to the inspection results.

Repair or replace the malfunctioning parts according to the inspection results.

Perform the Variable Swirl System Operation Inspection.

(See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L3 Turbo].)

Does the variable swirl system work properly?

Yes

Go to the next step.

Repair or replace the malfunctioning parts according to the inspection results.

Perform the Variable Valve Timing Control System Operation Inspection.

(See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L3 Turbo].)

Does the variable valve timing control system work properly?

Yes

Go to the next step.

Repair or replace the malfunctioning parts according to the inspection results.

Perform the Purge Control System Inspection.

(See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L3 Turbo].)

Does the purge solenoid valve work properly?

Yes

Go to the next step.

Repair or replace the malfunctioning parts according to the inspection results.

Perform the Fuel Pump Speed Control Inspection.

(See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L3 Turbo].)

Does the fuel pump speed control work properly?

Yes

Go to the next step.

Repair or replace the malfunctioning parts according to the inspection results.

Perform the Wastegate Control System Operation Inspection.

(See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L3 Turbo].)

Does the wastegate control system work properly?

Yes

Go to the next step.

Repair or replace the malfunctioning parts according to the inspection results.

Access the following PIDs using the M-MDS:

(See ON-BOARD DIAGNOSTIC TEST [L3 Turbo].)

• BAT

• ECT

• MAF

• IAT

• APP1

• APP2

• TP REL

• MAP

• FP (Low side pressure line)

• VSS

Do the PID values indicate the correct values under the trouble condition?

(See PCM INSPECTION [L3 Turbo].)

Yes

Go to the next step.

Inspect the suspected parts and related wiring harness.

• If normal:

― Perform the “INTERMITTENT CONCERN TROUBLESHOOTING.

(See INTERMITTENT CONCERN TROUBLESHOOTING [L3 Turbo].)

• If not:

― Repair or replace the malfunctioning parts according to the inspection results.

Inspect the CMP sensor and CKP sensor for the following:

• Installation condition

(See CAMSHAFT POSITION (CMP) SENSOR REMOVAL/INSTALLATION [L3 Turbo].)

(See CRANKSHAFT POSITION (CKP) SENSOR REMOVAL/INSTALLATION [L3 Turbo].)

• Damaged trigger wheel and camshaft

• Open or short circuit in the wiring harnesses

Is there any malfunction?

Yes

Repair or replace the malfunctioning parts according to the inspection results.

Go to the next step.

Inspect the spark plug condition.

Is the spark plug wet, covered with carbon or grayish white?

Yes

Spark plug is wet or covered with carbon:

• Perform the Spark Test.

(See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L3 Turbo].)

• Repair or replace the malfunctioning parts according to the inspection results.

Spark plug is grayish white:

• Go to Step 25.

Reinstall the spark plugs on the original cylinders, then go to the next step.

Inspect for restriction in the exhaust system and TWC.

Is there any restriction?

Yes

Repair or replace the malfunctioning parts according to the inspection results.

Go to the next step.

Remove the parts necessary to inspect the turbocharger without removing the turbocharger.

(See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3 Turbo].)

Inspect if the turbocharger compressor wheel is bent, damaged, or interfering with housing on vehicle.

(See TURBOCHARGER INSPECTION [L3 Turbo].)

Is there any malfunction?

Yes

Replace the turbocharger.

(See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3 Turbo].)

Go to the next step.

Inspect the turbocharger compressor wheel locknut is loose or has fallen down inside the turbocharger.

Is there any malfunction?

Yes

Replace the turbocharger.

(See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3 Turbo].)

Go to the next step.

Inspect the turbocharger compressor wheel by hand.

Does the wheel turn easily and smoothly?

Yes

Go to the next step.

Replace the turbocharger.

(See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3 Turbo].)

Inspect the turbocharger turbine wheel is damaged, cracked or interfering with housing on vehicle.

Note

• Inspect all fins on each turbine wheel.

Is there any malfunction?

Yes

Replace the turbocharger.

(See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3 Turbo].)

Go to the next step.

Is any engine oil found inside the turbocharger turbine housing?

Yes

Excessive amount of oil is found:

• Replace the turbocharger.

(See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3 Turbo].)

Small amount of oil is found:

• Wipe the oil out of the vehicle, then go to the next step.

Go to the next step.

Is any engine oil found inside the turbocharger compressor housing?

Yes

Wipe the oil out of the vehicle and install all removed parts in Step 17, then go to the next step.

Turbocharger is normal:

• Install all removed parts in Step 17, then go to the next step.

Inspect for fuel leakage in the fuel line.

Is there any leakage?

Yes

Repair or replace the malfunctioning parts according to the inspection results.

Go to the next step.

Access the FUEL_PRES PID using the M-MDS.

(See ON-BOARD DIAGNOSTIC TEST [L3 Turbo].)

Is the FUEL_PRES PID value within the specification?

(See PCM INSPECTION [L3 Turbo].)

Yes

Go to Step 28.

Go to the next step.

Replace the high pressure fuel pump.

(See HIGH PRESSURE FUEL PUMP REMOVAL/INSTALLATION [L3 Turbo].)

Access the FUEL_PRES PID using the M-MDS.

(See ON-BOARD DIAGNOSTIC TEST [L3 Turbo].)

Is the FUEL_PRES PID value within the specified?

(See PCM INSPECTION [L3 Turbo].)

Yes

High-pressure fuel pump or spill valve control solenoid valve (built-in high pressure fuel pump) malfunction.

Relief valve or fuel pressure sensor malfunction.

• Replace the fuel delivery pipe.

(See FUEL INJECTOR REMOVAL/INSTALLATION [L3 Turbo].)

Connect the fuel pressure gauge between the fuel pump and the high pressure fuel pump.

Measure the fuel pressure line of the low pressure side.

(See FUEL LINE PRESSURE INSPECTION [L3 Turbo].)

Is the fuel pressure within the specification?

Yes

Go to the next step.

Inspect for the following:

• Fuel line restriction

• Fuel filter clogging

• If normal:

― Replace the fuel pump unit.

(See FUEL PUMP UNIT REMOVAL/INSTALLATION [L3 Turbo].)

• If not:

― Repair or replace the malfunctioning parts according to the inspection results.

Perform the Fuel Injector Operation Inspection.

(See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L3 Turbo].)

Do the fuel injectors operate normally?

Yes

Go to the next step.

Repair or replace the malfunctioning parts according to the inspection results.

Measure the compression pressure for each cylinder.

(See COMPRESSION INSPECTION [L3 Turbo].)

Are compression pressures within the specification?

Yes

Go to the next step.

Inspect for the following:

• Damaged valve seat

• Worn valve stem and valve guide

• Worn or stuck piston ring

• Worn piston, piston ring or cylinder

• Improper valve timing

Repair or replace the malfunctioning parts according to the inspection results.

Inspect the PCV valve.

(See POSITIVE CRANKCASE VENTILATION (PCV) VALVE INSPECTION [L3 Turbo].)

Is there any malfunction?

Yes

Replace the PCV valve.

(See POSITIVE CRANKCASE VENTILATION (PCV) VALVE REMOVAL/INSTALLATION [L3 Turbo].)

Replace the PCM (injector driver circuit malfunction).

(See PCM REMOVAL/INSTALLATION [L3 Turbo].)

• If a malfunction remains:

― Repair or replace the malfunctioning part according to the inspection results.

Verify test results.

• If normal, return to the diagnostic index to service any additional symptoms.

• If a malfunction remains, inspect the related Service Information and perform the repair or diagnosis.

― If the vehicle is repaired, troubleshooting is completed.

― If the vehicle is not repaired or additional diagnostic information is not available, reprogram the PCM if a later calibration is available. Retest.