NO.12 LACK/LOSS OF POWER-ACCELERATION/CRUISE [MZR-CD (RF Turbo)]


BME010300000W47

12

LACK/LOSS OF POWER-ACCELERATION CRUISE

DESCRIPTION

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

POSSIBLE CAUSE

• Poor fuel quality
• Air leakage from intake-air system
• Intake-air system restriction
• Air cleaner restriction
• Engine overheating
• A/C system improper operation
• Improper operation of A/C cut-off control
• Variable boost control (VBC) system malfunction
• Variable swirl control (VSC) system malfunction
• EGR system malfunction
• Vacuum leakage
• Clutch slippage
• Exhaust system and/or catalyst converter restriction
• Fuel line restriction
• Fuel filter clogging
• Incorrect fuel injection timing
• Erratic signal from CKP sensor
• Erratic signal from CMP sensor
• ECT sensor or related circuit malfunction
• Boost sensor or related circuit malfunction
• Accelerator position sensor or related circuit malfunction
• MAF/IAT sensor or related circuit malfunction
• IAT sensor No.2 or related circuit malfunction
• Intermittent open or short circuit MAF sensor, accelerator position sensor, idle switch and VSS
• Incorrect adjustment accelerator position sensor and/or idle switch
• Incorrect idle speed
• Inadequate fuel pressure
• Fuel pressure sensor or related circuit malfunction
• Suction control valve malfunction (built-in supply pump)
• Fuel pressure limiter malfunction (built-in common rail)
• Supply pump malfunction
• Fuel injector malfunction
• Low engine compression
• Turbocharger malfunction
• Charge air cooler malfunction
• Brake system dragging
• Intake shutter valve malfunction
• Guide blade valve malfunction
• IDM or related circuit malfunction
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 REPAIR PROCEDURE" and "AFTER REPAIR PROCEDURE" described in this manual.

Diagnostic Procedure

STEP

INSPECTION

RESULTS

ACTION

1
Is idle speed stable?
Yes
Go to next step.
No
Go to symptom troubleshooting "NO.8 ENGINE RUNS ROUGH/ROLLING IDLE".
2
Is engine overheating?
Yes
Go to symptom troubleshooting "NO.17 COOLING SYSTEM CONCERNS-OVERHEATING".
No
Go to next step.
3
Perform self-test function using WDS or equivalent.
Turn engine switch to ON.
Retrieve any DTC.
Is DTC displayed?
Yes

DTC is displayed:

Go to appropriate DTC test.

Communication error message is displayed:

Inspect for following:
• Open circuit between PCM control relay and PCM terminal 53 or 79
• Open circuit PCM control relay and PCM terminal 69
• PCM control relay stuck open
• Open or poor GND circuit (PCM terminal 65, 85, 103 or 104)
• Poor connection vehicle body GND
No

No DTC is displayed:

Go to next step.
4
Inspect for followings:
• Fuel quality (e.g.: including water contamination, winter/summer blend)
• Fuel line/fuel filter clogging and/or restriction
• Intake-air system restriction
• Exhaust system and/or catalyst converter restriction
• Charge air cooler condition (restriction or damaged)
• Vacuum leakage
Are all items okay?
Yes
Go to next step.
No
Service as necessary.
Repeat Step 4.
5
Inspect intake shutter valve and VSC valve operations.
Is there any problem?
Yes
Repair or replace as necessary.
No
Go to next step.
6
Inspect guide blade valve operation.
Is there any problem?
Yes
Repair or replace as necessary.
No
Go to next step.
7
Inspect A/C cut-off operation.
Does A/C cut-off work properly?
Yes
Go to next step.
No
Repair or replace malfunctioning part according to A/C cut-off system inspection results.
8
Inspect hose bands between following parts:
• Turbocharger compressor housing and air cleaner
• Turbocharger compressor housing and charge air cooler
Are hose bands loose?
Yes
Retighten hose bands.
If concern is resolved, complete inspection.
If concern still exists, go to next step.
No
Go to next step.
9
Inspect for improper operation, kinks, clogging or disconnection on guide blade actuator.
Is actuator okay?
Yes
Go to next step.
No
Repair or replace as necessary.
If concern is resolved, complete inspection.
If concern still exists, turbocharger is okay.
Go to next step.
10
Remove parts necessary to inspect turbocharger.
Do not remove turbocharger.
Inspect if turbocharger compressor wheel is bent, damaged, or interfering with housing on vehicle.
Is there any problem?
Yes
Replace turbocharger.
No
Go to next step.
11
Inspect if turbocharger compressor wheel locknut is loose or has fallen down inside turbocharger.
Is there any problem?
Yes
Replace turbocharger.
No
Go to next step.
12
Inspect if turbocharger compressor wheel by hand.
Does wheel turn easily and smoothly?
Yes
Go to next step.
No
Replace turbocharger.
13
Inspect if turbocharger turbine wheel is damaged, cracked or interfering with housing on vehicle.
Note
• Inspect all fins on each turbine wheel.
Is there any problem?
Yes
Replace turbocharger.
No
Go to next step.
14
Is any engine oil found inside turbocharger turbine housing?
Yes

Excessive amount of oil is found:

Replace turbocharger.

Small amount of oil is found:

Wipe oil off of vehicle, then go to next step.
No
Go to next step.
15
Is any engine oil found inside turbocharger compressor hosing?
Yes
Wipe oil off of vehicle and install all removed parts in Step 10. Then, go to next step.
No
Turbocharger is okay.
Install all parts removed in Step10.
Then, go to next step.
16
Perform EGR system inspection.
Is EGR system okay?
Yes
Go to next step.
No
Repair or replace malfunctioning part according to EGR system operation results.
17
Inspect idle speed.
Is idle speed correct?
Yes
Go to next step.
No
Repair or replace malfunctioning part according to idle speed inspection results.
18
Inspect adjustment of accelerator position sensor and idle switch.
Are accelerator position sensor and idle switch adjusted correctly?
Yes
Go to next step.
No
Adjust accelerator position sensor and idle switch correctly.
19
Visually inspect CKP sensor and teeth of pulse wheel.
Are CKP sensor and teeth of pulse wheel okay?
Yes
Go to next step.
No
Replace malfunctioning parts.
20
Measure gap between CKP sensor and teeth of pulse wheel.

Specification

1.5-2.5 mm {0.059-0.098 in}

Is gap within specification?
Yes
Go to next step.
No
Adjust CKP sensor position.
21
Visually inspect CMP sensor and teeth of pulse wheel.
Are CMP sensor and teeth of pulse wheel okay?
Yes
Inspect following PIDs:
• ECT
• IAT
• MAF
• MAP
• RPM
If PID value is not as specified, repair or replace malfunctioning parts.
If PID value is okay, go to next step.
No
Replace malfunctioning parts.
22
Inspect fuel pressure sensor.
Is fuel pressure okay?
Yes
Go to next step.
No
Replace common rail.
23
Inspect suction control valve.
Is suction control valve okay?
Yes
Go to next step.
No
Repair supply pump.
24
Is engine compression correct?
Yes
Go to next step.
No
Inspect for followings:
• Damaged valve seat
• Worn valve stem and valve guide
• Worn or stuck piston ring
• Worn piston, piston ring or cylinder
• Improper valve timing
Service as necessary.
25
Inspect fuel injector.
Is fuel injector okay?
Yes
Go to next step.
No
Repair or replace as necessary.
26
Inspect timing belt for following:
• Chipping of gear teeth
• Low tension
• Breakage damage or cracks
Is timing belt okay?
Yes
Inspect following:
• Clutch slippage
• CKP sensor
• Boost sensor and related circuit
• Brake system for dragging
If okay, remove and inspect supply pump and common rail.
No
If valve timing is incorrect, adjust valve timing.
If timing belt is not okay, replace timing belt.
27
Verify test results.
• If okay, return to diagnostic index to service any additional symptoms.
• If malfunction remains, replace PCM. (See PCM REMOVAL/INSTALLATION [MZR-CD (RF Turbo)].)