No. 19 Exhaust Smoke [MZI-3.7]: Notes

WARNING: This page is about a different car, the 2009 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

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 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 servicing fuel system: 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 Service Information. (See BEFORE SERVICE PRECAUTION [MZI-3.7] .) (See AFTER SERVICE PRECAUTION [MZI-3.7] .) CAUTION: Disconnecting/connecting quick release connector without cleaning it may 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.

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 servicing fuel system:
- 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 Service Information.
  (See BEFORE SERVICE PRECAUTION [MZI-3.7] .)
  
  (See AFTER SERVICE PRECAUTION [MZI-3.7] .)
CAUTION:
- Disconnecting/connecting quick release connector without cleaning it may 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.