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DTC P219B: Air-fuel Ratio Imbalance (bank 2)
 
 
 
 
TECHNICAL DESCRIPTION
It is thought that the air-fuel ratio between cylinders is uneven due to a deviation or a difference in combustion environment between cylinders.
 
 
MONITOR EXECUTION
  • Continuous
 
 
MONITOR EXECUTION CONDITIONS (Other monitor and Sensor)
Other Monitor (There is no temporary DTC set in memory for the item monitored below)
  • Left bank linear air-fuel ratio sensor monitor
  • Left bank linear air-fuel ratio sensor heater monitor
  • Misfire monitor
Sensor (The sensor below is determined to be normal)
  • Mass airflow sensor
  • Engine coolant temperature sensor
  • Intake air temperature sensor
  • Barometric pressure sensor
  • Throttle position sensor
  • Manifold absolute pressure sensor
 
 
DTC SET CONDITIONS
Logic Flow Chart
 
 
Check Conditions
  • Under the closed loop air-fuel control.
  • Engine speed is between 1,500 r/min and 4,000 r/min.
  • Volumetric efficiency is between 40 and 100 percent.
  • Left bank linear air-fuel ratio sensor output is between 13.1 and 16.0.
  • Short-term fuel trim is between -25 and +25 percent.
  • Engine coolant temperature is higher than 60°C (140°F).
  • 0.2 second or more has elapsed after the above mentioned conditions have been met.
Judgment Criteria
  • The number of rich/lean air-fuel ratio peak is more than the specified amount.
  • During the drive cycle, the ECM performs monitoring with the accumulated total ignition of 600, 5 times.
 
 
FAIL-SAFE AND BACKUP FUNCTION
  • None
 
 
OBD-II DRIVE CYCLE PATTERN
  • Refer to Diagnosis Function - OBD-II Drive Cycle - Pattern 26 .
 
 
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are: )
  • Injector failed.
  • Contaminated intake ports.
  • There is some foreign matter around intake and exhaust valves.
  • Ignition system related part(s) failed.
  • Poor compression.
  • Left bank linear air-fuel ratio sensor failed.
  • ECM failed.

 
 
DIAGNOSIS
STEP 1. Using scan tool (M.U.T.-III), read the diagnostic trouble code (DTC).
cautionTo prevent damage to scan tool (M.U.T.-III), always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool (M.U.T.-III).
(1) Connect scan tool (M.U.T.-III). Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III) .
(2) Turn the ignition switch to the "ON" position.
(3) Read the DTC.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Is the diagnostic trouble code other than P219B set?
Refer to Diagnostic Trouble Code Chart .
Go to Step 2.
 
STEP 2. Check the left bank ignition coil spark.
(1) Remove the ignition coil.
(2) Remove the spark plug and connect to the ignition coil.
(3) Ground the spark plug side electrode securely.
  • When the engine is cranked, the spark plug should spark.
Did it spark?
Go to Step 3.
Refer to Symptom Procedure - Ignition Circuit System .
 
STEP 3. Check the compression.
Refer to GROUP 11C, On-vehicle Service - Compression Pressure Check .
Are there any abnormalities?
Repair it. Then go to Step 10.
Go to Step 4.
 
STEP 4. Check the left bank injector.
Refer to Injector check .
Is the measured resistance normal?
Go to Step 5.
Replace the faulty injector. Then go to Step 10.
 
STEP 5. Check the intake manifold, intake manifold plenum and the intake ports contamination.
Are the intake manifold, intake manifold plenum and the intake ports clogged?
Repair the intake manifold, intake manifold plenum and the intake ports contamination. Then go to Step 10.
Go to Step 6.
 
STEP 6. Check for foreign matter being around the intake and exhaust valves.
Are there any foreign matter?
Repair it. Then go to Step 10.
Go to Step 7.
 
STEP 7. Check of harness damage in LHFL, LRL, LSFL, LEFL and LPFL line between left bank linear air-fuel ratio sensor and ECM connector.
Is the harness wire in good condition?
Go to Step 8.
Repair the connector(s) or wiring harness. Then go to Step 10.
 
STEP 8. Replace the left bank linear air-fuel ratio sensor.
(1) Replace the left bank linear air-fuel ratio sensor.
(2) Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 26 .
(3) Check the diagnostic trouble code (DTC).
Is DTC P219B set?
Go to Step 9.
The inspection is complete.
 
STEP 9. Replace the left bank injector.
(1) Replace the left bank injector.
(2) Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 26 .
(3) Check the diagnostic trouble code (DTC).
Is DTC P219B set?
Replace the ECM (Refer to Removal and Installation ). Then go to Step 10.
The inspection is complete.
 
STEP 10. Test the OBD-II drive cycle.
(1) Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 26 .
(2) Check the diagnostic trouble code (DTC).
Is DTC P219B set?
Retry the troubleshooting.
The inspection is complete.