Page 1537 of 3051
3 CHECK IDLE SPEED
With CONSULT-II
1. Select ªCKPS´RPM (TDC)º in ªDATA MONITORº mode with CONSULT-II.
2. Read idle speed.
SEF817Y
Without CONSULT-II
Check idle speed.
750±25 rpm
OK or NG
OK©INSPECTION END
NG©GO TO 4.
4 CHECK FOR INTAKE AIR LEAK
Listen for an intake air leak after the mass air flow sensor.
OK or NG
OK©GO TO 5.
NG©Repair or replace.
5 BLEED AIR FROM FUEL SYSTEM
1. Stop engine.
2. Use priming pump to bleed air from fuel system. Refer to ªAIR BLEEDINGº, EC-1094.
©GO TO 6.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONYD22DDTI
Basic Inspection (Cont'd)
EC-1112
Page 1538 of 3051
6 CHECK IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and let it idle.
2. Select ªCKPS´RPM (TDC)º in ªDATA MONITORº mode with CONSULT-II.
3. Read idle speed.
SEF817Y
Without CONSULT-II
1. Start engine and let it idle.
2. Check idle speed.
750±25 rpm
OK or NG
OK©INSPECTION END
NG©GO TO 7.
7 DRIN WATER FROM FUEL FILTER
Drain water from fuel filter. Refer to ªWATER DRAININGº, EC-1094.
©GO TO 8.
8 CHECK IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and let it idle.
2. Select ªCKPS´RPM (TDC)º in ªDATA MONITORº mode with CONSULT-II.
3. Read idle speed.
SEF817Y
Without CONSULT-II
1. Start engine and let it idle.
2. Check idle speed.
750±25 rpm
OK or NG
OK©INSPECTION END
NG©GO TO 9.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONYD22DDTI
Basic Inspection (Cont'd)
EC-1113
Page 1539 of 3051
9 CHECK AIR CLEANER FILTER
Check air cleaner filter for clogging or braks.
OK or NG
OK©GO TO 10.
NG©Replace air cleaner filter.
10 CHECK FUEL INJECTION NOZZLE
Check fuel injection nozzle opening pressure. Refer to ªInjection Pressure Testº, EC-1086.
OK or NG
OK©GO TO 11.
NG©Replace fuel injection nozzle assembly.
11 CHECK IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and let it idle.
2. Select ªCKPS´RPM (TDC)º in ªDATA MONITORº mode with CONSULT-II.
3. Read idle speed.
SEF817Y
Without CONSULT-II
1. Start engine and let it idle.
2. Check idle speed.
750±25 rpm
OK or NG
OK©INSPECTION END
NG©GO TO 12.
12 CHECK COMPRESSION PRESSURE
Check compression pressure. Refer to EM-164, ªMEASUREMENT OF COMPRESSION PRESSUREº.
OK or NG
OK©GO TO 13.
NG©Follow the instruction of ªMEASUREMENT OF COMPRESSION PRESSUREº.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONYD22DDTI
Basic Inspection (Cont'd)
EC-1114
Page 1540 of 3051
13 CHECK IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and let it idle.
2. Select ªCKPS´RPM (TDC)º in ªDATA MONITORº mode with CONSULT-II.
3. Read idle speed.
SEF817Y
Without CONSULT-II
1. Start engine and let it idle.
2. Check idle speed.
750±25 rpm
OK or NG
OK©INSPECTION END
NG©Replace electronic control fuel injection pump.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONYD22DDTI
Basic Inspection (Cont'd)
EC-1115
Page 1541 of 3051

Symptom Matrix ChartNLEC1257
SYSTEM Ð Basic engine
control systemSYMPTOM
Reference page
Feature of symptom, Check pointHARD/NO START/RESTART
(EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
KNOCK/DETONATION
LACK OF POWER
POOR ACCELERATION
HI IDLE
LOW IDLE NO START (with first firing)
NO START (without first firing)
HARD TO START WHEN ENGINE IS COLD
HARD TO START WHEN ENGINE IS HOT
AT IDLE
DURING DRIVING
WHEN DECELERATINGWarranty symptom code AA AB AC AD AE AF
Electronic control fuel injec-
tion pump mainframe4444444445544 Ð *1
Injection nozzle3333333334433EC-1083 *2
Glow system1111 1EC-1267
Engine body3333333 344 3EMsection *3
EGR system3 3 EC-1277
Swirl control system 3 3 EC-1285
Air cleaner and ducts 3 3 MA section *4
1 - 5: The numbers refer to the order of inspection.
(continued on next page)
*1: Fuel injection system malfunction or fuel injection timing control system malfunction may be the cause.
*2: Depends on open-valve pressure and spray pattern.
*3: Caused mainly by insufficient compression pressure.
*4: Symptom varies depending on off-position of air duct, etc.
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONYD22DDTI
Symptom Matrix Chart
EC-1116
Page 1542 of 3051

SYSTEM Ð Basic engine control
systemSYMPTOM
Reference page
Feature of symptom, Check pointROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEAT/HIGH ENGINE COOLANT TEMPERATURE
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
ABNORMAL SMOKE COLOR
DEAD BATTERY (UNDER CHARGE)
Malfunction indicator illuminates.
Can be detected by CONSULT-II?BLACK SMOKE
WHITE SMOKEWarranty symptom code AG AH AJ AK AL AM AP HA
Electronic control fuel injection
pump mainframe44345433Ð*1
Injection nozzle 3 3 3 4 3 EC-1083 *2
Glow system 1 1 EC-1267
Engine body 3 3 3 3 3 3 EM section *3
EGR system 3 EC-1277
Swirl control system 3 3 3 EC-1285
Air cleaner and ducts 3 3 MA section *4
1 - 5: The numbers refer to the order of inspection.
(continued on next page)
*1: Fuel injection system malfunction or fuel injection timing control system malfunction may be the cause.
*2: Depends on open-valve pressure and spray pattern.
*3: Caused mainly by insufficient compression pressure.
*4: Symptom varies depending on off-position of air duct, etc.
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONYD22DDTI
Symptom Matrix Chart (Cont'd)
EC-1117
Page 1543 of 3051

SYSTEM Ð ENGINE CONTROL system
Malfunction
SYMPTOM
Reference page
Feature of symptom, Check pointHARD/NO START/RESTART
(EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
KNOCK/DETONATION
LACK OF POWER
POOR ACCELERATION
HI IDLE
LOW IDLE NO START (with first firing)
NO START (without first firing)
HARD TO START WHEN ENGINE IS COLD
HARD TO START WHEN ENGINE IS HOT
AT IDLE
DURING DRIVING
WHEN DECELERATINGWarranty symptom code AA AB AC AD AE AF
ENGINE CONTROL
Electronic control fuel injection
pump circuit*a, *b 1 1
111111111
Ð
*c, *d
Mass air flow sensor circuit*a, *c
111
EC-1143
*b
Engine coolant temperature sensor
circuit*a, *b 1 1 1 1 EC-1150 *1
Vehicle speed sensor circuit *a, *b 1 EC-1172
1 - 5: The numbers refer to the order of inspection.
(continued on next page)
*a: Open
*b: Short
*c: Ground short
*d: Noise
*1: Compensation according to engine coolant temperature does not function.
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONYD22DDTI
Symptom Matrix Chart (Cont'd)
EC-1118
Page 1544 of 3051
SYSTEM Ð ENGINE CONTROL system
Malfunction
SYMPTOM
Reference page
Feature of symptom, Check pointROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEAT/HIGH ENGINE COOLANT TEMPERATURE
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
ABNORMAL SMOKE COLOR
DEAD BATTERY (UNDER CHARGE)
Malfunction indicator illuminates.
Can be detected by CONSULT-II?BLACK SMOKE
WHITE SMOKEWarranty symptom code AG AH AJ AK AL AM AP HA
ENGINE CONTROL
Electronic control fuel injection pump
circuit*a, *b 1 1 1
11 Ð
*c, *d 1
Mass air flow sensor circuit*a, *c
1 EC-1143
*b 1
Engine coolant temperature sensor cir-
cuit*a, *b 1 1 1 1 1 EC-1150 *1
Vehicle speed sensor circuit *a, *b 1 EC-1172
1 - 5: The numbers refer to the order of inspection.
(continued on next page)
*a: Open
*b: Short
*c: Ground short
*d: Noise
*1: Compensation according to engine coolant temperature does not function.
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONYD22DDTI
Symptom Matrix Chart (Cont'd)
EC-1119