P0301
Misfire Detected Circuit- Refer to DTC P0201, P0203, P0205 - Injector Circuit.
- Refer to DTC P0202, P0204, P0206 - Injector Circuit.
CIRCUIT OPERATION
- Refer to DTC P0201 ,P0203,P0205 - Injector Circuit.
- Refer to DTC P0202,P0204,P0206 - Injector Circuit.
TECHNICAL DESCRIPTION
- If a misfire occurs while the engine is running, the engine speed changes for an instant.
- The ECM
DTC SET CONDITIONS
Check Conditions
- Five seconds or more have passed after the engine was started.
- Engine speed is between 440 and 6,000 r/min.
- Engine coolant temperature is higher than -10 °C (14 °F).
- Intake air temperature is higher than -10 °C (14 °F).
- Barometric pressure is at between 77 kPa (11 psi) and 106 kPa (15 psi).
- 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.
- Vehicle speed is 2.5 km/h (1.6 mph) or more.
- The throttle deviation is -0.059 v/10 ms to +0.059 v/10 ms.
Judgement Criteria (change in the angular acceleration of the crankshaft is used for misfire detection).
- Misfire has occurred in 4 or more of the last 200 revolutions [when the catalyst temperature is higher than 950 °C (1,742 °F)].
or
- Misfire has occurred in 20 or more of the last 1,000 revolutions (corresponding to 1.5 times the limit of emission standard).
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- Ignition system related part(s) failed.
- Low compression pressure.
- Injector failed.
- ECM failed.
- PCM failed.
DIAGNOSIS
Required Special Tools
MB991502: Scan Tool(MUT-II)
STEP 1. Check the spark plugs.
CAUTION: Do not attempt to adjust the gap of the platinum plug. Cleaning of the platinum plug may result in damage to the platinum tips. Therefore, if carbon deposits must be removed, use a plug cleaner and complete cleaning within 20 seconds to protect the electrode. Do not use a wire brush.
1. For the right bank cylinder, remove the intake manifold.
2. Check the plug gap and replace if the limit is exceeded.
Standard value: 1.0 - 1.1 mm (0.039 - 0.043 inch)
Limit: 1.3 mm (0.051 inch)
Q: Is the plug gap at the standard value?
YES: Go to Step 2.
NO: Replace the spark plug. Then go to Step 9.
STEP 2. Check the spark plug cable.
1. Check the cap and coating for cracks.
2. Measure the resistance.
Limit: maximum 22 kOhms
Q: Is the resistance normal?
YES: Go to Step 3.
NO: Replace the spark plug cable. Then go to Step 9.
STEP 3. Check the injector.
1. Disconnect the injector connector B-01
2. Measure the resistance between injector side connector terminal 1 and 2.
Standard value: 13 - 16 Ohms [at 20 °C (68 °F)]
Q: Is the resistance standard value?
YES: Go to Step 4.
NO: Replace the injector. Then go to Step 9
STEP 4. Check connector at injector and injector intermediate connector for damage.
a. Check the connector B-01 at injector and connector B-118 at injector intermediate connector when checking No.1 cylinder.
b. Check the connector B-02 at injector and connector B-118 at injector intermediate connector when checking No.2 cylinder.
c. Check the connector B-05 at injector and connector B-118 at injector intermediate connector when checking No.3 cylinder.
d. Check the connector B-06 at injector and connector B-118 at injector intermediate connector when checking No.4 cylinder.
e. Check the connector B-26 at injector and connector B-118 at injector intermediate connector when checking No.5 cylinder.
f. Check the connector B-25 at injector and connector B-118 at injector intermediate connector when checking No.6 cylinder.
Q: Is the connector in good condition?
YES: Go to Step 5.
NO: Repair or replace the injector. Refer to Harness Connector Inspection. Then go to Step 9.
STEP 5. Check connector C-111 at ECM
Q: Is the connector in good condition?
YES: Go to Step 6.
NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 9.
STEP 6. Check for harness damage between injector connector and ECM connector
a. Check the harness wire between injector connector B-01 terminal 2 and ECM connector C-111 terminal 1
b. Check the harness wire between injector connector B-02 terminal 2 and ECM connector C-111 terminal 9
c. Check the harness wire between injector connector B-05 terminal 2 and ECM connector C-111 terminal 24
d. Check the harness wire between injector connector B-06 terminal 2 and ECM connector C-111 terminal 2
e. Check the harness wire between injector connector B-26 terminal 2 and ECM connector C-111 terminal 10
f. Check the harness wire between injector connector B-25 terminal 2 and ECM connector C-111 terminal 25
Q: Is the harness wire in good condition?
YES: Go to Step 7.
NO: Repair it. Then go to Step 9.
STEP 7. Check the compression.
Q: Are there any abnormalities?
YES: Go to Step 8.
NO: Repair or replace it. Then go to Step 9.
STEP 8. Replace the injector.
1. Replace the injector.
2. Carry out a test drive with the drive cycle pattern. Refer to Procedure 6 - Other Monitor.
3. Check the diagnostic trouble code (DTC).
Q: Is the DTC P0301, P0302, P0303, P0304, P0305, P0306 is output?
YES: Replace the ECM or PCM. Then go to Step 9.
NO: The inspection is complete.
STEP 9. Test the OBD-II drive cycle.
1. Carry out a test drive with the drive cycle pattern. Refer to Procedure 6 - Other Monitor.
2. Check the diagnostic trouble code(DTC).
Q:Is the DTC P0301, P0302, P0303, P0304, P0305, P0306 is output?
YES: Retry the troubleshooting.
NO: The inspection is complete.