Code No. P0302: No. 2 Cylinder Misfire Detected

OPERATION

Refer to Code No. P0202 No. 2 Injector System .

FUNCTION

If a misfire occurs while the engine is running, the engine speed changes for an instant.
The engine-ECU checks for such changes in engine speed.

TROUBLE JUDGMENT

Check Conditions

Engine speed is 500 - 6,500 r/min.
Engine coolant temperature is -10°C or higher.
Barometric pressure is 76 kPa or higher.
Volumetric efficiency is between 30 % and 55 %.
Adaptive learning is complete for the vane which generates a crankshaft position signal.
While the engine is running, excluding gear shifting, deceleration, sudden acceleration/deceleration and A/C compressor switching.
The throttle deviation is -0.06 V/10 ms to +0.06 V/10 ms.

Judgment Criterion (change in the angular acceleration of the crankshaft is used for misfire detection).

Misfire has occurred more frequently than the limit during the last 200 revolutions (when the catalyst temperature has been 950°C or higher).

Misfire has occurred 15 times or more in the last 1,000 revolutions (that has been equivalent to approximately 1.5 times the emission standard).

PROBABLE CAUSES

Ignition system related part(s) failed
Low compression pressure
Failed engine-ECU
Failed fuel system
Harness damage in No. 2 injector circuit, or connector damage

DIAGNOSIS PROCEDURE

STEP 1. Visual check of ignition spark.

Remove the spark plug and install to the ignition coil.
Connect the ignition coil connector.
Remove all injector connectors.
At the engine start, check each spark plug procedure a spark.

Q. Is the check result normal?

	Go to Step 2 .

	Check ignition circuit system (Refer to Inspection Procedure 32 <134>, Inspection Procedure 33 <3A9>).

STEP 2. Check connector: A-102 No. 2 injector connector

Q. Is the check result normal?

Go to Step 3 .

Repair or replace the connector.

STEP 3. Check No. 2 injector itself.

Check Injector itself (Refer to ).

Q. Is the check result normal?

	Go to Step 4 .

	Replace the No. 2 injector.

STEP 4. Connector check: B-206 engine control relay connector and A-08 engine-ECU connector

Q. Is the check result normal?

Go to Step 5 .

Repair or replace the connector.

STEP 5. Check harness between B-206 (terminal No. 4) engine control relay connector and A-102 (terminal No. 1) No. 2 injector connector.

note

Before checking harness, check intermediate connectors A-13 and B-212, and repair if necessary.

Check power supply line for damage.

Q. Is the check result normal?

Go to Step 6 .

Repair the damaged harness wire.

STEP 6. Check harness between A-102 (terminal No. 2) No. 2 injector connector and A-08 (terminal No. 9) engine-ECU connector

Check earthing line for damage.

Q. Is the check result normal?

Go to Step 7 .

Repair the damaged harness wire.

STEP 7. Fuel pressure measurement.

Fuel pressure measurement (Refer to Fuel Pressure Test )

Q. Is the check result normal?

	Go to Step 8 .

	Repair the fuel pressure.

STEP 8. Check compression pressure.

Check compression pressure (Refer to GROUP 11A - On-vehicle Service - Compression Pressure Check ).

Q. Is the check result normal?

	Go to Step 9 .

	Repair the compression pressure.

STEP 9. M.U.T.-III diagnosis code

Reconfirmation of diagnosis code.

Q. Is the diagnosis code set?

	Replace the engine-ECU then perform the variant coding (Refer to GROUP 00 - Precautions Before Service - How to Perform Variant Coding ).

	Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).