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DTC P219A: Air-fuel Ratio Imbalance
 
 
 
 
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)
  • Not applicable
Sensor (The sensor below is determined to be normal)
  • Not applicable
 
 
DTC SET CONDITIONS
Logic Flow Chart
 
 
Check Conditions
  • Under the closed loop air-fuel control.
  • Engine speed is between 1,500 r/min and 3,000 r/min.
  • Volumetric efficiency is between 50 and 160 percent.
  • Linear air-fuel ratio sensor output is between 13.5 and 15.5.
  • Fuel injection mode is not MFI-mode.
  • 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 400, 5 times.
 
 
FAIL-SAFE AND BACKUP FUNCTION
  • None.
 
 
OBD-II DRIVE CYCLE PATTERN
  • Refer to Diagnosis Function - OBD-II Drive Cycle - Pattern 8 .
 
 
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
  • Injector failed.
  • Injector (high pressure) failed.
  • Contaminated intake ports.
  • There is some foreign matter around intake and exhaust valves.
  • Ignition system related part(s) failed.
  • Poor compression.
  • Linear air-fuel ratio sensor failed.
  • ECM failed.

 
 
DIAGNOSIS
STEP 1. Using scan tool (M.U.T.-IIISE), read the diagnostic trouble code (DTC).
cautionTo prevent damage to scan tool (M.U.T.-IIISE), always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool (M.U.T.-IIISE).
(1) Connect scan tool (M.U.T.-IIISE). Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-IIISE) .
(2) Turn the ignition switch to the "ON" position.
(3) Read the DFI and MFI-DTC.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Is the diagnostic trouble code other than P219A set?
Refer to Diagnostic Trouble Code Chart .
Go to Step 2.
 
STEP 2. Visual check of ignition spark.
(1) Remove the spark plug and install it to the ignition coil.
(2) Connect the ignition coil connector.
(3) Remove all injector connector.
(4) At the engine start, check each spark plug produces a spark.
Did it spark?
Go to Step 3.
Refer to Symptom Procedures - Ignition Circuit System .
 
STEP 3. Check the compression.
Refer to GROUP 11A, On-vehicle Service - Compression Pressure Check .
Are there any abnormalities?
Repair it. Then go to Step 13.
Go to Step 4.
 
STEP 4. Check the injector.
Refer to Injector check .
Is the measured resistance normal?
Go to Step 5.
Replace the faulty injector. Then go to Step 13.
 
STEP 5. Check the intake manifold contamination and the intake ports contamination.
Are the intake manifold and the intake ports clogged?
Repair the intake manifold and the intake ports contamination. Then go to Step 13.
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 13.
Go to Step 7.
 
STEP 7. Check the injector (high pressure).
Refer to Injector (high pressure) Check .
Is the measured resistance normal?
Go to Step 8.
Replace the faulty injector (high pressure). Then go to Step 13.
 
STEP 8. Check high-pressure fuel line.
By a visual inspection and odor inspection, check around the high-pressure fuel line from the fuel pump (high pressure) to the injector (high pressure). Ensure that there is not fuel seepage and fuel leaks.
Are there any abnormalities?
Repair it. Then go to Step 13.
Go to Step 9.
 
STEP 9. Check of harness damage in LHFL, LRL, LSFL, LEFL and LPFL line between linear air-fuel ratio sensor and ECM connector.
Is the harness wire in good condition?
Go to Step 10.
Repair the connector(s) or wiring harness. Then go to Step 13.
 
STEP 10. Replace the linear air-fuel ratio sensor.
(1) Replace the 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 8 .
(3) Check the diagnostic trouble code (DTC).
Is DTC P219A set?
Go to Step 11.
The inspection is complete.
 
STEP 11. Replace the injector.
(1) Replace the injector.
(2) Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 8 .
(3) Check the diagnostic trouble code (DTC).
Is DTC P219A set?
Go to Step 12.
The inspection is complete.
 
STEP 12. Replace the injector (high pressure).
(1) Replace the injector (high pressure).
(2) Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 8 .
(3) Check the diagnostic trouble code (DTC).
Is DTC P219A set?
Replace the ECM (Refer to Removal and Installation ). Then go to Step 13.
The inspection is complete.
 
STEP 13. 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 8 .
(2) Check the diagnostic trouble code (DTC).
Is DTC P219A set?
Retry the troubleshooting.
The inspection is complete.