DTC Advanced Diagnostics: P219C, P219D, P219E, P219F

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

General Description 

Courtesy of HONDA, U.S.A., INC.

Courtesy of HONDA, U.S.A., INC.

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:
  1. -

     Fuel coefficient of each cylinder is higher than the threshold value: Failure on corresponding cylinder

  2. -

     Fuel coefficient of each cylinder is lower than the threshold value: Pass

• When the imbalance amount is a specified value (about 10 %) or more:
  1. -

     Performs imbalance reduction control and fuel coefficient is higher than the threshold value: failure on corresponding cylinder

  2. -

     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]	155.9°F (68.8°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	-	50 rpm
Fuel trim	0.69	1.47
Intake air amount variation	-	0.06 g (0.0021 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 1.16 or more.

Possible Cause 

• 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 

Courtesy of HONDA, U.S.A., INC.

• Start the engine. Hold the engine speed [Engine Speed] at 3,000 rpm without load (in P or N) until the radiator fan comes on, then let it idle.
• Drive the vehicle in 4th gear or more at a steady engine speed [Engine Speed] 1,000 - 1,200 rpm.
• Take 10 - 15 seconds to accelerate up to engine speed [Engine Speed] 3,400 rpm.
• 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.

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, the freeze data, and the on-board snapshot 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, the freeze data, and the on-board snapshot can be cleared with the scan tool clear command.