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


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 pedal 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 pedal position sensor, idle switch and VSS • Incorrect adjustment accelerator pedal 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 SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZR-CD (RF Turbo)].) (See AFTER SERVICE PRECAUTION [MZR-CD (RF Turbo)].)


STEP	INSPECTION	RESULTS	ACTION
1	Is idle speed stable?	Yes	Go to the next step.
1	Is idle speed stable?	No	Go to symptom troubleshooting "NO.8 ENGINE RUNS ROUGH/ROLLING IDLE". (See NO.8 ENGINE RUNS ROUGH/ROLLING IDLE [MZR-CD (RF Turbo)].)
2	Is the engine overheating?	Yes	Go to symptom troubleshooting "NO.17 COOLING SYSTEM CONCERNS-OVERHEATING". (See NO.17 COOLING SYSTEM CONCERNS-OVERHEATING [MZR-CD (RF Turbo)].)
2	Is the engine overheating?	No	Go to the next step.
3	Perform self-test function using the WDS or equivalent. Turn the engine switch to the ON position. Retrieve any DTC. Is DTC displayed?	Yes	DTC is displayed: Go to the applicable DTC inspection. (See DTC TABLE [MZR-CD (RF Turbo)].) Communication error message is displayed: Inspect for the 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
3		No	No DTC is displayed: Go to the next step.
4	Inspect for the 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 normal?	Yes	Go to the next step.
4		No	Service if necessary. Repeat Step 4.
5	Inspect the intake shutter valve and the VSC valve operations. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [MZR-CD (RF Turbo)].) Is there any problem?	Yes	Repair or replace if necessary.
5		No	Go to the next step.
6	Inspect the guide blade valve operation. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [MZR-CD (RF Turbo)].) Is there any problem?	Yes	Repair or replace if necessary.
6		No	Go to the next step.
7	Inspect the A/C cut-off operation. Does the A/C cut-off work properly?	Yes	Go to the next step.
7		No	Repair or replace the malfunctioning part according to the A/C cut-off system inspection results.
8	Inspect hose bands between the 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 the inspection. If concern still exists, go to the next step.
8		No	Go to the next step.
9	Inspect for improper operation, kinks, clogging or disconnection on the guide blade actuator. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [MZR-CD (RF Turbo)].) Is the actuator normal?	Yes	Go to the next step.
9		No	Repair or replace if necessary. If concern is resolved, complete the inspection. If concern still exists, the turbocharger is normal. Go to the next step.
10	Note • Do not remove the turbocharger. Remove parts for easier access to inspect the turbocharger. Inspect if the turbocharger compressor wheel is bent, damaged, or interfering with housing on the vehicle. Is there any problem?	Yes	Replace the turbocharger.
10		No	Go to the next step.
11	Inspect if the turbocharger compressor wheel locknut is loose or has fallen down inside the turbocharger. Is there any problem?	Yes	Replace the turbocharger.
11		No	Go to the next step.
12	Inspect if the turbocharger compressor wheel by hand. Does the wheel turn easily and smoothly?	Yes	Go to the next step.
12		No	Replace the turbocharger.
13	Inspect if the turbocharger turbine wheel is damaged, cracked or interfering with housing on the vehicle. Note • Inspect all fins on each turbine wheel. Is there any problem?	Yes	Replace the turbocharger.
13		No	Go to the next step.
14	Is any engine oil found inside the turbocharger turbine housing?	Yes	Excessive amount of oil is found: Replace the turbocharger. Small amount of oil is found: Wipe off oil of the vehicle, then go to the next step.
14		No	Go to the next step.
15	Is any engine oil found inside the turbocharger compressor hosing?	Yes	Wipe oil off of vehicle and install all removed parts in Step 10. Then, go to the next step.
15		No	The turbocharger is normal. Install all parts removed in Step10. Then, go to the next step.
16	Perform the EGR system inspection. Is the EGR system normal?	Yes	Go to the next step.
16		No	Repair or replace the malfunctioning part according to the EGR system operation results.
17	Inspect idle speed. (See IDLE SPEED INSPECTION [MZR-CD (RF Turbo)].) Is idle speed correct?	Yes	Go to the next step.
17		No	Repair or replace the malfunctioning part according to the idle speed inspection results.
18	Inspect adjustment of the accelerator pedal position sensor and the idle switch. (See ACCELERATOR PEDAL POSITION (APP) SENSOR INSPECTION [MZR-CD (RF Turbo)].) (See IDLE SWITCH INSPECTION [MZR-CD (RF Turbo)].) Are the accelerator pedal position sensor and the idle switch adjusted correctly?	Yes	Go to the next step.
18		No	Adjust the accelerator pedal position sensor and the idle switch correctly. (See ACCELERATOR PEDAL POSITION (APP) SENSOR INSPECTION [MZR-CD (RF Turbo)].) (See IDLE SWITCH ADJUSTMENT [MZR-CD (RF Turbo)].)
19	Visually inspect the CKP sensor and teeth of the pulse wheel. Are the CKP sensor and teeth of the pulse wheel normal?	Yes	Go to the next step.
19		No	Replace the malfunctioning parts.
20	Measure the gap between the CKP sensor and teeth of the pulse wheel. Specification 1.5-2.5 mm {0.059-0.098 in} Is the gap within the specification?	Yes	Go to the next step.
20		No	Adjust the CKP sensor position.
21	Visually inspect the CMP sensor and teeth of the pulse wheel. Are the CMP sensor and teeth of the pulse wheel normal?	Yes	Inspect the following PIDs: (See PCM INSPECTION [MZR-CD (RF Turbo)].) • ECT • IAT • MAF • MAP • RPM If PID value is not as specified, repair or replace the malfunctioning part. If PID value is normal, go to the next step.
21		No	Replace malfunctioning parts.
22	Inspect the fuel pressure sensor. (See FUEL PRESSURE SENSOR INSPECTION [MZR-CD (RF Turbo)].) Is fuel pressure normal?	Yes	Go to the next step.
22		No	Replace the common rail.
23	Inspect the suction control valve. (See SUCTION CONTROL VALVE INSPECTION [MZR-CD (RF Turbo)].) Is the suction control valve normal?	Yes	Go to the next step.
23		No	Repair the supply pump. (See SUPPLY PUMP INSPECTION [MZR-CD (RF Turbo)].)
24	Is the engine compression correct? (See COMPRESSION INSPECTION [MZR-CD (RF Turbo)].)	Yes	Go to the next step.
24		No	Inspect for the 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 if necessary.
25	Inspect the fuel injector. (See FUEL INJECTOR INSPECTION [MZR-CD (RF Turbo)].) Is the fuel injector normal?	Yes	Go to the next step.
25		No	Repair or replace normal necessary.
26	Inspect the timing belt for the following: • Chipping of gear teeth • Low tension • Breakage damage or cracks Is the timing belt normal?	Yes	Inspect the following: • Clutch slippage • CKP sensor • Boost sensor and related circuit • Brake system for dragging If normal, remove and inspect the supply pump and the common rail.
26		No	If valve timing is incorrect, adjust valve timing. If the timing belt is not normal, replace the timing belt.
27	Verify test results. • If normal, return to diagnostic index to service any additional symptoms. • If malfunction remains, replace the PCM. (See PCM REMOVAL/INSTALLATION [MZR-CD (RF Turbo)].)