NO.26 EXHAUST SULPHUR SMELL [MZI-3.7]

id0103d2803200

26

EXHAUST SULPHUR SMELL
DESCRIPTION
•  Rotten egg smell (sulphur) from exhaust.
POSSIBLE CAUSE
•  Electrical connectors are disconnected or connected poorly.
•  Vacuum lines are disconnected or connected improperly.
•  Poor fuel quality
•  PCM DTC is stored.
•  Improper fuel line pressure
―  Intermittent open or short circuit in fuel pump circuit
―  Fuel pump mechanical malfunction
―  Fuel line restriction or clogging
―  Pressure regulator malfunction (built-in fuel pump unit)
•  Charcoal canister malfunction
Warning
•  The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the 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 manual. (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.

Diagnostic procedure

STEP

INSPECTION

RESULTS

ACTION
1
Are any driveability or exhaust smoke concerns present?
Yes
Go to the appropriate symptom troubleshooting.
(See SYMPTOM DIAGNOSTIC INDEX [MZI-3.7].)
No
Go to the next step.
2
Inspect the following:
•  Electrical connections
•  Vacuum lines
•  Fuel quality
Are all items normal?
Yes
Go to the next step.
No
Repair or replace the malfunctioning part according to the inspection results.
Repeat Step 2.
3
Turn the ignition switch to the ON position (Engine off).
Retrieve any PCM DTCs using the M-MDS.
(See ON-BOARD DIAGNOSTIC TEST [MZI-3.7 (PCM CONNECTOR (2 TYPES))].)
(See ON-BOARD DIAGNOSTIC TEST [MZI-3.7 (PCM CONNECTOR (3 TYPES))].)
Are there any DTCs displayed?
Yes
DTC is displayed:
•  Go to the appropriate DTC inspection.
No
No DTC is displayed:
•  Go to the next step.
4
Install the fuel pressure gauge between fuel pipe and fuel distributor.
Start the engine and run it at idle.
Measure the fuel line pressure during idle.
(See FUEL LINE PRESSURE INSPECTION [MZI-3.7].)
Is the fuel line pressure correct during idle?
Yes
Go to the next step.
No
Zero or low:
•  Inspect the following:
―  Fuel pump relay
―  Fuel pump circuit
―  Fuel line for clogging
•  If there is no malfunction, replace the fuel pump unit. (Fuel pump or pressure regulator malfunction)
High:
•  Replace the fuel pump unit. (Pressure regulator malfunction)
5
Inspect the charcoal canister for fuel saturation.
Is excess amount of liquid fuel present in canister?
Yes
Replace the charcoal canister.
(See CHARCOAL CANISTER, CANISTER VENT (CV) SOLENOID VALVE, AIR FILTER COMPONENT REMOVAL/INSTALLATION [MZI-3.7].)
No
Inspect the fuel tank vent system.
(See FUEL TANK INSPECTION [MZI-3.7].)
Repair or replace the malfunctioning part according to the inspection results.
•  If the fuel tank vent system is normal, suggest trying a different brand since sulphur content can vary in different fuels.
6
•  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 the PCM.