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NO.19 EXHAUST SMOKE [L3]

BME010300103257

19 | EXHAUST SMOKE
--- | ---
DESCRIPTION | Blue, black, or white smoke from exhaust system
POSSIBLE CAUSE | Blue smoke (Burning oil): • PCV valve malfunction • Engine internal oil leakage White smoke (Water in combustion): • Cooling system malfunction (coolant loss)
• Engine internal coolant leakage

Black smoke (Rich fuel mixture):

• Air cleaner restriction
• Intake-air system is collapsed or restricted.
• Fuel return line is restricted.
• Excessive fuel pressure
• Improper engine compression
• Injector fuel leakage
• Ignition system malfunction

  Warning
The following troubleshooting flow chart contains fuel system diagnosis and repair procedures. Read following warnings before performing 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 injuries 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 [L3].)
  (See AFTER SERVICE PRECAUTION [L3].)

  Caution

  • Disconnecting/connecting quick release connector without cleaning it may possibly cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.

Diagnostic procedure

STEP | INSPECTION | RESULTS | ACTION
--- | --- | --- | ---
1 | What color is smoke coming from the exhaust system? | Blue | Burning oil is indicated. Go to the next step.
White | Water in combustion is indicated. Go to Step 3.
Black | Rich fuel mixture is indicated. Go to Step 4.
2 | Remove and shake the PCV valve. Does the PCV valve rattle? | Yes | Inspect for the following: • Damaged valve guide, stems or valve seals • Blocked oil drain passage in cylinder head • Piston ring is not seated, seized or worn. • Damaged cylinder bore
If other driveability symptoms are present, return to the diagnostic index to service any additional symptoms.
No | Replace the PCV valve.
3 | Does the cooling system hold pressure? | Yes | Inspect for the following: • Cylinder head gasket leakage • Intake manifold gasket leakage • Cracked or porous engine block If other driveability symptoms are present, return to the diagnostic index to service any additional symptoms.
No | Inspect for cause.
4 | Inspect for the following: • Air cleaner restriction • Collapsed or restricted intake-air system • Restricted fuel return line Are all items normal? | Yes | Go to the next step.
No | Service if necessary. Repeat Step 4.
5 | Connect the WDS or equivalent to the DLC-2. Retrieve any continuous memory, KOEO and KOER DTCs. Are there any DTCs displayed? | Yes | DTC is displayed: Go to the applicable DTC inspection. (See DTC TABLE [L3].)
No | No DTC is displayed: Go to the next step.
6 | Install fuel pressure gauge between fuel pipe and fuel distributor. Start the engine and run it at idle. Measure fuel line pressure at idle. Is fuel line pressure correct at idle? (See FUEL LINE PRESSURE INSPECTION [L3].) | Yes | Go to the next step.
No | Zero or low: • Inspect for clogged fuel line. • If normal, replace the fuel pump unit. (See FUEL PUMP UNIT REMOVAL/INSTALLATION [L3].) High:
• Replace the fuel pump unit.
(See FUEL PUMP UNIT REMOVAL/INSTALLATION [L3].)
7 | Is strong blue spark visible at each disconnected high-tension lead while cranking the engine? | Yes | Inspect spark plugs and the CMP sensor.
No | Inspect the following: • High-tension leads • Ignition coil and connector
8 | Verify test results. • If normal, return to diagnostic index to service any additional symptoms. • If malfunction remains, replace PCM.