NO.4 HARD START/LONG CRANK/ERRATIC START/ERRATIC CRANK [MZ-CD 1.6 (Y6)]

4	HARD START/LONG CRANK/ERRATIC START/ERRATIC CRANK
DESCRIPTION	• The starter cranks the engine at the normal speed but the engine requires excessive cranking time before starting. • The battery is normal.
POSSIBLE CAUSE	• Poor fuel quality • Intake-air system restriction or clogging • Starting system malfunction • Inadequate fuel pressure • Fuel pressure limiter malfunction • Fuel metering valve malfunction • Engine overheating • Glow system malfunction • Fuel filter clogging or restriction • Fuel line clogging or restriction • Fuel leakage • Fuel warmer system malfunction • Exhaust system and/or catalyst converter restriction or clogging • Incorrect fuel injection timing • Erratic signal from CKP sensor • Erratic signal from CMP sensor • ECT sensor or related circuit malfunction • Accelerator pedal 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 • EGR system malfunction • Diesel particulate filter restriction or damaged (High power-Euro 4) • Diesel particulate filter system malfunction (High power-Euro 4) Предупреждение The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: • 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.

HARD START/LONG CRANK/ERRATIC START/ERRATIC CRANK

DESCRIPTION

• The starter cranks the engine at the normal speed but the engine requires excessive cranking time before starting.

• The battery is normal.

POSSIBLE CAUSE

• Poor fuel quality

• Intake-air system restriction or clogging

• Starting system malfunction

• Inadequate fuel pressure

• Fuel pressure limiter malfunction

• Fuel metering valve malfunction

• Engine overheating

• Glow system malfunction

• Fuel filter clogging or restriction

• Fuel line clogging or restriction

• Fuel leakage

• Fuel warmer system malfunction

• Exhaust system and/or catalyst converter restriction or clogging

• Incorrect fuel injection timing

• Erratic signal from CKP sensor

• Erratic signal from CMP sensor

• ECT sensor or related circuit malfunction

• Accelerator pedal 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

• EGR system malfunction

• Diesel particulate filter restriction or damaged (High power-Euro 4)

• Diesel particulate filter system malfunction (High power-Euro 4)

Предупреждение

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

• 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.

STEP	INSPECTION	RESULTS	ACTION
1	Inspect the following: • Fuel quality (e.g.: include water contamination, winter/summer blend) • Fuel line/fuel filter clogging • Intake-air system restriction Are all the items normal?	Yes	Go to the next step.
No	Service if necessary. Repeat Step 1.
2	Is the engine overheating?	Yes	Go to symptom troubleshooting “NO.17 COOLING SYSTEM CONCERNS-OVERHEATING”.
No	Go to the next step.
3	Connect the M-MDS to the DLC-2. Turn the engine switch to the ON position. Retrieve any DTC. Are DTCs displayed?	Yes	DTC is displayed: Go to appropriate DTC test. Communication error message is displayed: Inspect for the following: • Open circuit between PCM control relay and PCM terminal 236 or 231 • Open circuit between PCM control relay and PCM terminal 241 • PCM control relay stuck open • Open or poor ground circuit (PCM terminal 307, 308 or 332) • Poorly connected vehicle body GND
No	No DTC is displayed: Go to the next step.
4	Does the engine start normally after warm-up?	Yes	Go to the next step.
No	Go to Step 7.
5	Inspect glow system operation Is the glow system operation normal?	Yes	Go to the next step.
No	Repair or replace malfunctioning parts according to the glow system operation inspection results.
6	Inspect fuel warmer system operation. Is the fuel warmer system operation normal?	Yes	Go to the next step.
No	Repair or replace malfunctioning parts according to the fuel warmer system operation inspection results.
7	Is there any restriction in the exhaust system, catalyst converter or diesel particulate filter^*?	Yes	Repair or replace if necessary.
No	Go to the next step.
8	Inspect for fuel leakage from the fuel pipe Is any fuel leakage found on the fuel pipe?	Yes	Repair or replace if necessary.
No	Go to the next step.
9	Connect the M-MDS to the DLC-2. Access the following PIDs. • APP Verify that the PID value when the accelerator pedal is depressed and/or released. Is PID indicate value normal?	Yes	Go to the next step.
No	Inspect and repair or replace following parts: • Accelerator pedal position sensor
10	Visually inspect CKP sensor and teeth of pulse wheel Are the CKP sensor and the teeth of the pulse wheel normal?	Yes	Go to the next step.
No	Replace malfunctioning parts.
11	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 the next step.
No	Adjust CKP sensor position.
12	Visually inspect CMP sensor and teeth of pulse wheel Are the CMP sensor and the teeth of the pulse wheel normal?	Yes	Inspect the following PIDs: (See PCM INSPECTION [MZ-CD 1.6 (Y6)].) • ECT • IAT • MAF • RPM If the PID value is not as specified, repair or replace malfunctioning parts. If the PID value is normal, go to the next step.
No	Replace malfunctioning parts.
13	Inspect fuel pressure sensor (See FUEL PRESSURE SENSOR INSPECTION [MZ-CD 1.6 (Y6)].) Is the fuel pressure normal?	Yes	Go to the next step.
No	Replace the common rail.
14	Inspect fuel metering valve (See ПРОВЕРКА ДОЗИРУЮЩЕГО КЛАПАНА [MZ-CD 1.6 (Y6)].) Is the fuel metering valve normal?	Yes	Go to the next step.
No	Replace the fuel pump. (See СНЯТИЕ И УСТАНОВКА ТНВД [MZ-CD 1.6 (Y6)].)
15	Is the engine compression correct?	Yes	Go to the next step.
No	Inspect the following: • Damaged valve seat • Worn valve stem and valve guide • Worn or stuck piston ring • Worn piston, piston ring or cylinder Service if necessary.
16	Inspect fuel injector (See ПРОВЕРКА ТОПЛИВНЫХ ФОРСУНОК [MZ-CD 1.6 (Y6)].) Is fuel injector normal?	Yes	Go to the next step.
No	Repair or replace if necessary.
17	Inspect EGR system operation. Is the EGR system operation normal?	Yes	Go to step 23. (standard power-Euro 4) Go to the next step. (High power-Euro 4)
No	Repair or replace the malfunctioning part according to the EGR system operation results.
18	Check scheduled maintenance for following: • Fuel additive • Diesel particulate filter Are these scheduled maintenances properly?	Yes	Go to the next step.
No	Carry out the scheduled maintenance properly.
19	Inspect the fuel additive amount. Are there any fuel additives in fuel additive tank?	Yes	Go to the next step.
No	Inspect and repair or replace for following: • Fuel additive hose (Fuel additive tank - fuel additive pump - fuel tank) • Fuel tank level sensor
20	Remove the diesel particulate filter. Visually inspect for damaged at diesel particulate filter. Are there detected any damaged?	Yes	Replace the diesel particulate filter.
No	Go to the next step.
21	Perform cooling air bypass valve operation inspection. Does the cooling air bypass valve operation properly?	Yes	Go to the next step.
No	Repair or replace malfunctioning part, according to inspection result.
22	Access following PIDs using the M-MDS. • CABVDC • CABVP • DPF_DIF • POST_CAT Monitor the PIDs. Are there any problems detected?	Yes	Inspect the suspect PID related wiring and components. If okay inspect the fuel level sensor.
No	Go to the next step.
23	Inspect starting system. Is the starting system normal?	Yes	Inspect for loose connectors or poor terminal contact. If normal, remove and inspect the supply pump and common rail.
No	Repair or replace components if necessary.
24	Verify test results. • If normal, return to the diagnostic index to service any additional symptoms. (See SYMPTOM DIAGNOSTIC INDEX [MZ-CD 1.6 (Y6)].) • If the malfunction remains, inspect related Service Information and perform repair or diagnosis. ― If the vehicle is repaired, troubleshooting is completed. ― If the vehicle is not repaired or additional diagnostic information is not available, replace the PCM. (See PCM REMOVAL/INSTALLATION [MZ-CD 1.6 (Y6)].)

STEP

INSPECTION

RESULTS

ACTION

Inspect the following:

• Fuel quality (e.g.: include water contamination, winter/summer blend)

• Fuel line/fuel filter clogging

• Intake-air system restriction

Are all the items normal?

Yes

Go to the next step.

Service if necessary.

Repeat Step 1.

Is the engine overheating?

Yes

Go to symptom troubleshooting “NO.17 COOLING SYSTEM CONCERNS-OVERHEATING”.

Go to the next step.

Connect the M-MDS to the DLC-2.

Turn the engine switch to the ON position.

Retrieve any DTC.

Are DTCs displayed?

Yes

DTC is displayed:

Go to appropriate DTC test.

Communication error message is displayed:

Inspect for the following:

• Open circuit between PCM control relay and PCM terminal 236 or 231

• Open circuit between PCM control relay and PCM terminal 241

• PCM control relay stuck open

• Open or poor ground circuit (PCM terminal 307, 308 or 332)

• Poorly connected vehicle body GND

No DTC is displayed:

Go to the next step.

Does the engine start normally after warm-up?

Yes

Go to the next step.

Go to Step 7.

Inspect glow system operation

Is the glow system operation normal?

Yes

Go to the next step.

Repair or replace malfunctioning parts according to the glow system operation inspection results.

Inspect fuel warmer system operation.

Is the fuel warmer system operation normal?

Yes

Go to the next step.

Repair or replace malfunctioning parts according to the fuel warmer system operation inspection results.

Is there any restriction in the exhaust system, catalyst converter or diesel particulate filter^*?

Yes

Repair or replace if necessary.

Go to the next step.

Inspect for fuel leakage from the fuel pipe

Is any fuel leakage found on the fuel pipe?

Yes

Repair or replace if necessary.

Go to the next step.

Connect the M-MDS to the DLC-2. Access the following PIDs.

• APP

Verify that the PID value when the accelerator pedal is depressed and/or released.

Is PID indicate value normal?

Yes

Go to the next step.

Inspect and repair or replace following parts:

• Accelerator pedal position sensor

Visually inspect CKP sensor and teeth of pulse wheel

Are the CKP sensor and the teeth of the pulse wheel normal?

Yes

Go to the next step.

Replace malfunctioning parts.

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 the next step.

Adjust CKP sensor position.

Visually inspect CMP sensor and teeth of pulse wheel

Are the CMP sensor and the teeth of the pulse wheel normal?

Yes

Inspect the following PIDs:

(See PCM INSPECTION [MZ-CD 1.6 (Y6)].)

• ECT

• IAT

• MAF

• RPM

If the PID value is not as specified, repair or replace malfunctioning parts.

If the PID value is normal, go to the next step.

Replace malfunctioning parts.

Inspect fuel pressure sensor

(See FUEL PRESSURE SENSOR INSPECTION [MZ-CD 1.6 (Y6)].)

Is the fuel pressure normal?

Yes

Go to the next step.

Replace the common rail.

Inspect fuel metering valve

(See ПРОВЕРКА ДОЗИРУЮЩЕГО КЛАПАНА [MZ-CD 1.6 (Y6)].)

Is the fuel metering valve normal?

Yes

Go to the next step.

Replace the fuel pump.

(See СНЯТИЕ И УСТАНОВКА ТНВД [MZ-CD 1.6 (Y6)].)

Is the engine compression correct?

Yes

Go to the next step.

Inspect the following:

• Damaged valve seat

• Worn valve stem and valve guide

• Worn or stuck piston ring

• Worn piston, piston ring or cylinder

Service if necessary.

Inspect fuel injector

(See ПРОВЕРКА ТОПЛИВНЫХ ФОРСУНОК [MZ-CD 1.6 (Y6)].)

Is fuel injector normal?

Yes

Go to the next step.

Repair or replace if necessary.

Inspect EGR system operation.

Is the EGR system operation normal?

Yes

Go to step 23. (standard power-Euro 4)

Go to the next step. (High power-Euro 4)

Repair or replace the malfunctioning part according to the EGR system operation results.

Check scheduled maintenance for following:

• Fuel additive

• Diesel particulate filter

Are these scheduled maintenances properly?

Yes

Go to the next step.

Carry out the scheduled maintenance properly.

Inspect the fuel additive amount.

Are there any fuel additives in fuel additive tank?

Yes

Go to the next step.

Inspect and repair or replace for following:

• Fuel additive hose (Fuel additive tank - fuel additive pump - fuel tank)

• Fuel tank level sensor

Remove the diesel particulate filter.

Visually inspect for damaged at diesel particulate filter.

Are there detected any damaged?

Yes

Replace the diesel particulate filter.

Go to the next step.

Perform cooling air bypass valve operation inspection.

Does the cooling air bypass valve operation properly?

Yes

Go to the next step.

Repair or replace malfunctioning part, according to inspection result.

Access following PIDs using the M-MDS.

• CABVDC

• CABVP

• DPF_DIF

• POST_CAT

Monitor the PIDs.

Are there any problems detected?

Yes

Inspect the suspect PID related wiring and components.

If okay inspect the fuel level sensor.

Go to the next step.

Inspect starting system.

Is the starting system normal?

Yes

Inspect for loose connectors or poor terminal contact.

If normal, remove and inspect the supply pump and common rail.

Repair or replace components if necessary.

Verify test results.

• If normal, return to the diagnostic index to service any additional symptoms. (See SYMPTOM DIAGNOSTIC INDEX [MZ-CD 1.6 (Y6)].)

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

― If the vehicle is repaired, troubleshooting is completed.

― If the vehicle is not repaired or additional diagnostic information is not available, replace the PCM. (See PCM REMOVAL/INSTALLATION [MZ-CD 1.6 (Y6)].)