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No.19 Exhaust Smoke: Notes

EXHAUST SMOKE - DESCRIPTION AND POSSIBLE CAUSE

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
Injector fuel leakage
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 REPAIR PROCEDURE" and "AFTER REPAIR PROCEDURE" described in this manual.
    (See BEFORE REPAIR PROCEDURE .)
    
    (See AFTER REPAIR PROCEDURE .)