NO.19 EXHAUST SMOKE [ZJ, ZY, Z6]

id0103b1803900

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 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 the "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual.
Caution
•  If there is foreign material on the connecting area of the quick release connector, it might damage the connector or fuel pipe. To prevent this, disconnect the connector and clean the connecting area before connecting.

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 drivability symptoms are present, return to 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 drivability symptoms are present, return to 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 M-MDS to the DLC-2.
Retrieve any continuous memory, KOEO and KOER DTCs using M-MDS.
Are there any DTCs displayed?
Yes
DTC is displayed:
Go to the appropriate DTC inspection.
(See DTC TABLE[ZJ, ZY, Z6].)
No
No DTC is displayed:
Go to the next step.
6
Install fuel pressure gauge between the fuel pipe and the fuel distributor.
Start the engine and idle it.
Measure fuel line pressure during idle.
Is fuel line pressure correct during idle?
(See FUEL LINE PRESSURE INSPECTION[ZJ, ZY, Z6].)
Yes
Go to the next step.
No
Low:
Inspect the fuel line for clogging.
•  If there is no malfunction, replace fuel pump unit.
High:
Replace fuel pump unit.
(See FUEL PUMP UNIT REMOVAL/INSTALLATION[ZJ, ZY, Z6].)
7
Perform the spark test.
(See ENGINE CONTROL SYSTEM OPERATION INSPECTION[ZJ, ZY, Z6].)
Is strong blue spark visible at each cylinder?
Yes
Inspect the CMP sensor.
(See CAMSHAFT POSITION (CMP) SENSOR INSPECTION[ZJ, ZY, Z6].)
No
Repair or replace the malfunctioning part according to spark test result.
8
Verify test results.
•  If normal, return to diagnostic index to service any additional symptoms.
•  If malfunction remains, inspect related Service information perform repair or diagnosis.
―  If vehicle repaired, troubleshooting completed.
―  If vehicle not repaired or additional diagnostic information not available, replace the PCM.