Inspection Procedure 10

Inspection procedure 10: When the engine is cold, it stalls at idle (die out)

COMMENT
- In such cases as the above, the air/fuel mixture may be inappropriate when the engine is cold.

TROUBLESHOOTING HINTS (The most likely causes for this case:)
- Fuel pump system failed.
- Ignition system failed.
- Poor compression.
- Improper engine oil viscosity.
- ECM failed.

DIAGNOSIS

Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991910: Main Harness A

STEP 1. Using scan tool MB991958, read the diagnostic trouble code (DTC).






CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.

1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Read the DTC.
4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is any DTC set?

YES : Refer to, Diagnostic Trouble Code Chart. Diagnostic Trouble Code Descriptions

NO : Go to Step 2.

STEP 2. Using scan tool MB991958, check actuator test.

1. Turn the ignition switch to the "ON" position.

2. Check the following item in the actuator test. Refer to Actuator Test Reference Table Actuator Test Reference Table.
a. Item 1: Injectors

3. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Are they operating properly?

YES : Go to Step 3.

NO : Repair or replace it. Then confirm that the malfunction symptom is eliminated.

STEP 3. Using scan tool MB991958, check data list.

1. Turn the ignition switch to the "ON" position.

2. Check the following item in the data list. Refer to Data List Reference Table Datal List Reference Table.
a. Item 6: Engine Coolant Temperature Sensor

3. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the sensor operating properly?

YES : Go to Step 4.

NO : Repair or replace it. Then confirm that the malfunction symptom is eliminated.

STEP 4. Check the ignition timing.

Refer to On-vehicle Service - Ignition Timing Check. Testing and Inspection

Q: Is the ignition timing normal?

YES : Go to Step 5.

NO : Check for installed conditions of the timing chain. Then confirm that the malfunction symptom is eliminated.

STEP 5. Check the fuel pressure.

Refer to Fuel Pressure Test Testing and Inspection.

Q: Is the fuel pressure normal?

YES : Go to Step 6.

NO : Repair or replace it. Then confirm that the malfunction symptom is eliminated.

STEP 6. Check the spark plugs.

Refer to On-vehicle Service - Spark Plug Check and Cleaning. Testing and Inspection

Q: Are there any abnormalities?

YES : Replace the spark plug. Then confirm that the malfunction symptom is eliminated.

NO : Go to Step 7.

STEP 7. Check the ignition coil.

Refer to On-vehicle Service - Ignition Coil Check. Ignition Coil Check

Q: Are there any abnormalities?

YES : Replace the ignition coil. Then confirm that the malfunction symptom is eliminated.

NO : Go to Step 8.

STEP 8. Check the compression pressure.

Refer to On-vehicle Service - Compression Pressure Check. Compression Check

Q: Is the compression pressure normal?

YES : Check the engine oil viscosity, and replace the engine oil. Then confirm that the malfunction symptom is eliminated.

NO : Repair it. Then confirm that the malfunction symptom is eliminated.