DTC Advanced Diagnostics: P219C, P219D, P219E, P219F
DTC P219C:No. 1 Cylinder Air-Fuel Ratio Variation
DTC P219D:No. 2 Cylinder Air-Fuel Ratio Variation
DTC P219E:No. 3 Cylinder Air-Fuel Ratio Variation
DTC P219F:No. 4 Cylinder Air-Fuel Ratio Variation

General Description


The powertrain control module (PCM) detects the imbalance amount from the sizes of the 0.5-order and 1.0-order components compared to 0.8-order excitation input by the fuel injection to determine the air/fuel ratio variation between the cylinder. The obtained components are used to learn the fuel coefficient of each cylinder and performs the imbalance reduction control. If it is not possible to suppress the variation even if the imbalance reduction control is performed; resulting the imbalance amount is large and the fuel coefficient is a specified value or more, the PCM detects as imbalance failure.
When the imbalance amount is a specified value (about 10 %) or less:
?
Fuel coefficient of each cylinder is higher than the threshold value: Failure on corresponding cylinder
?
Fuel coefficient of each cylinder is lower than the threshold value: Pass
When the imbalance amount is a specified value (about 10 %) or more:
?
Performs imbalance reduction control and fuel coefficient is higher than the threshold value: Failure on corresponding cylinder
?
Performs imbalance reduction control and fuel coefficient of each cylinder is lower than the threshold value: Re-performs imbalance reduction control for a specified time and re-determines the failure by the fuel coefficient of each cylinder. If the imbalance amount is a specified value or less after imbalance reduction control is performed for a specified time, the determination is suspended. If the imbalance amount is a specified value or more after imbalance reduction control is performed for a specified time, the imbalance reduction control is performed again and if the fuel coefficient of each cylinder is higher than a specified value, the PCM detects the failure on corresponding cylinder.

Monitor Execution, Sequence, Duration, DTC Type
Execution
Once per driving cycle
Sequence
None
Duration
–
DTC Type
Two drive cycles, MIL on

Enable Conditions
Condition
Minimum
Maximum
Engine coolant temperature [ECT SENSOR 1]
156 °F (69 °C)
–
Intake air temperature
[IAT Sensor (1)]
-13 °F (-25 °C)
–
Engine speed [ENGINE SPEED]
1,350 rpm
3,400 rpm
Engine speed variation during 1 cycle
–
80 rpm
Fuel trim
0.75
1.47
Intake air amount variation
–
0.05 g (0.001 oz)
Fuel feedback
Closed loop at stoichiometric
Monitoring priority
P0133, P0420
[ ]: HDS Parameter

Malfunction Threshold
Fuel correction coefficient of each cylinder is 0.83 or less, or 1.15 or more.

Possible Cause
NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
Fuel injector failure
Fuel rail clogged
Intake manifold air leak/clogged
Cam lift failure
Ignition system failure
Engine compression abnormal
Valve clearance incorrect

Confirmation Procedure
Operating Condition

1.
Start the engine. Hold the engine speed [ENGINE SPEED] at 3,000 rpm without load (CVT in P or N, M/T in neutral) until the radiator fan comes on.
2.
Drive the vehicle in 4th gear at a steady engine speed [ENGINE SPEED] 1,000 - 1,200 rpm.
3.
Take 10 - 15 seconds to accelerate up to engine speed [ENGINE SPEED] 3,400 rpm.
4.
When the diagnosis does not finish, repeat Driving Pattern steps 2 through 3, five times.
Drive the vehicle in this manner only if the traffic regulations and ambient conditions allow.
With the HDS
None.

Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC and the freeze data are stored.

Conditions for clearing the DTC
The MIL is cleared if the malfunction does not return in three consecutive drive cycles in which the engine conditions are similar to the first time the malfunction was detected. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the 12 volt battery.