NO.19 EXHAUST SMOKE [AJ] (VIN: JMZ LW19J7*# 300001-, JM0 LW10J300 300001-301405, JM6 LW10J300 300001-, JM8 LW28J**# 300001-301513)


BME010300103224

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 is restricted.
• Intake-air system collapsed or restricted.
• Fuel return line is restricted.
• Excessive fuel pressure
• Improper engine compression
• Fuel leakage from fuel injector
• Ignition system malfunction
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 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 [AJ].)
(See AFTER SERVICE PRECAUTION [AJ].)

Diagnostic procedure

STEP

INSPECTION

ACTION

1
• What color is smoke coming from 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 rings are 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
• Engine block cracks or porosity
- 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.
• Turn the ignition switch to the ON position (Engine off).
• Retrieve any DTC.
• Is "PASSED" displayed?
Yes
No DTC displayed:
• Go to the next step.
No
DTC displayed:
• Go to the applicable DTC inspection.
6
• Install a fuel pressure gauge between the fuel filter and the fuel distributor.
• Start the engine and run it at idle.
• Measure fuel line pressure at idle.
• Is fuel line pressure correct at idle?
Yes
Go to the next step.
No
Zero or low:
• Inspect fuel pump circuit.
• Inspect for open fuel pump relief valve.
• Inspect for fuel leakage inside the pressure regulator.
• Inspect for clogged main fuel line.
High:
• Inspect the pressure regulator for high pressure cause.
• Inspect for clogged fuel return line.
7
• Is strong blue spark visible at each disconnected high-tension lead while cranking the engine?
Yes
Inspect the 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, inspect related Service Information and perform repair or diagnosis.
• If vehicle is repaired, troubleshooting completed.
• If vehicle is not repaired or additional diagnostic information is not available, replace or reprogram the PCM.