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NO.4 HARD START/LONG CRANK/ERRATIC START/ERRATIC CRANK [MZR-CD (RF Turbo)]

BME010300000W39

4 | HARD START/LONG CRANK/ERRATIC START/ERRATIC CRANK
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DESCRIPTION | • Starter cranks engine at normal speed but engine requires excessive cranking time before starting. • Battery is in normal condition.
POSSIBLE CAUSE | • Poor fuel quality • Intake-air system restriction • Starting system malfunction • Inadequate fuel pressure • Fuel pressure limiter malfunction (built-in common rail)
• Suction control valve malfunction (built-in supply pump)
• Engine overheating
• Glow system malfunction
• Fuel filter clogging
• Fuel line restriction
• Fuel leakage
• Exhaust system and/or catalyst converter restriction
• Incorrect fuel injection timing
• Erratic signal from CKP sensor
• Erratic signal from CMP sensor
• ECT sensor or related circuit malfunction
• Accelerator position sensor or related circuit malfunction
• MAF/IAT sensor or related circuit malfunction
• Fuel pressure sensor or related circuit malfunction
• Supply pump malfunction
• Fuel injector malfunction
• Low engine compression
• Improper valve timing
• IDM or related circuit malfunction
• EGR system malfunction
• Vacuum leakage

  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
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1 | Inspect for following: • Fuel quality (e.g.: include water contamination, winter/summer blend) • Fuel line/fuel filter clogging • Intake-air system restriction Are all items okay? | Yes | Go to next step.
No | Service as necessary. Repeat Step 1.
2 | Is engine overheating? | Yes | Go to symptom troubleshooting "NO.17 COOLING SYSTEM CONCERNS-OVERHEATING".
No | Go to next step.
3 | Connect WDS or equivalent to DLC-2. 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 followings: • 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 | Does engine start normally after warm-up? | Yes | Inspect glow system operation. (See RELAY INSPECTION.) Replace any malfunctioning part as necessary. If glow system is okay, go to next step.
No | Go to next step.
5 | Is there any restriction in exhaust system or catalyst converter? | Yes | Repair or replace as necessary.
No | Go to next step.
6 | Inspect for fuel leakage from fuel pipe. Is any fuel leakage found on fuel pipe? | Yes | Repair or replace as necessary.
No | Go to next step.
7 | 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.
8 | 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.
9 | Visually inspect CMP sensor and teeth of pulse wheel. Are CMP sensor and teeth of pulse wheel okay? | Yes | Inspect following PIDs: (See PCM INSPECTION [MZR-CD (RF Turbo)].) • ECT • IAT • MAF
• 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.
10 | Inspect fuel pressure sensor. (See FUEL PRESSURE SENSOR INSPECTION [MZR-CD (RF Turbo)].) Is fuel pressure okay? | Yes | Go to next step.
No | Replace common rail.
11 | Inspect suction control valve. (See SUCTION CONTROL VALVE INSPECTION [MZR-CD (RF Turbo)].) Is suction control valve okay? | Yes | Go to next step.
No | Repair supply pump. (See SUPPLY PUMP INSPECTION [MZR-CD (RF Turbo)].)
12 | Is engine compression correct? (See COMPRESSION INSPECTION [MZR-CD (RF Turbo)].) | Yes | Go to next step.
No | Inspect for following: • 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.
13 | Inspect fuel injector. (See FUEL INJECTOR INSPECTION [MZR-CD (RF Turbo)].) Is fuel injector okay? | Yes | Go to next step.
No | Repair or replace as necessary.
14 | Inspect EGR system operation. Is EGR system operation normal? | Yes | Go to next step.
No | Repair or replace malfunctioning part according to EGR system operation results.
15 | Inspect starting system. Is starting system normal? | Yes | Inspect for loose connectors or poor terminal contact. If okay, remove and inspect supply pump and common rail.
No | Repair or replace components as required.
16 | 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)].)