Diagnostic Trouble Code (DTC) P0300
Engine Misfire Detected
System Description
The Engine Control Module (ECM) monitors the crankshaft and camshaft positions to detect if the engine is misfiring. The ECM looks for a quick drop in crankshaft speed. This test is executed in blocks of 100 engine revolution tests. It may take between one to several tests to store a Diagnostic Trouble Code (DTC) and illuminate the Malfunction Indicator Lamp (MIL). Under light misfire conditions, it may also take more than one trip to set a DTC. Severe misfire will flash the MIL, indicating that catalyst damage is possible.
Conditions for Running the DTC
- Engine speed is between 0 and 4500 rpm.
- Engine load is greater than zero torque.
- Engine load change is less than maxium.
- Engine speed change is less than maxium.
- Intake air temperature is greater than -30 °C.
Conditions for Setting the DTC
- Misfire rate for emission relevant is more than 4 %.
- Misfire rate for catalyst damage is more than 1 %.
Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will be illuminated as soon as the error occurs.
- The ECM will record operating conditions at the time the diagnostic fail. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The MIL will turn off after three or four consecutive driving cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 consecutive warm up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for 10 seconds.
Diagnostic Aids
An intermittent can also be the result of a defective reluctor wheel. Remove the CKP sensor and inspect the reluctor wheel through the sensor mount hole. Check for porosity and the condition of wheel. If the DTC is intermittent refer to
"Symptoms Diagnosis" in this section.
DTC P0300 - Engine Misfire Detected
| Step | Action | Value(s) | Yes | No |
| 1 | Perform the Diagnostic System Check. Was the check performed? | - | Go to Step 2 | |
| 2 | - Perform a visual/physical inspection.
- Make any repairs that are necessary.
Is the repair complete? | - | Go to Step 26 | Go to Step 3 |
| 3 | Start the engine and allow it to idle. Are any current misfire counters incrementing? | - | Go to Step 4 | Go to Step 5 |
| 4 | Are all counters equal (within a percentage of each other)? | - | Go to Step 6 | Go to Step 10 |
| 5 | - Turn the ignition ON, with the engine OFF.
- Review the Freeze Frame data, and note the parameters.
- Operate the vehicle within the Freeze Frame conditions and conditions for setting this DTC as noted.
Are any Misfire Current counters incrementing? | - | Go to Step 4 | |
| 6 | - Turn the engine OFF.
- Install a fuel pressure gauge to the fuel rail.
- Observe the fuel pressure with the engine running.
Is the fuel pressure within the specified value? | 410 kPa | Go to Step 7 | |
| 7 | Check the fuel for contamination. Is the fuel OK? | - | Go to Step 8 | Go to Step 9 |
| 8 | Check for a basic engine problem and repair as necessary. Is the repair complete? | - | Go to Step 26 | - |
| 9 | Replace the contaminated fuel. Is the repair complete? | - | Go to Step 26 | - |
| 10 | - Turn the engine OFF.
- Disconnect the fuel injector harness connector.
- Crank the engine and check for spark.
Is a spark observed on all four spark plugs? | - | Go to Step 11 | Go to Step 19 |
| 11 | Replace any malfunctioning spark plugs if necessary. Is the repair complete? | - | Go to Step 26 | Go to Step 12 |
| 12 | - Turn the engine OFF.
- Disconnect the fuel injector connectors from the injectors.
- Install an injector test light on the injector harness connector for the cylinders that had misfired.
- Crank the engine and note the test light.
Does the injector test light blink? | - | Go to Step 13 | Go to Step 14 |
| 13 | Perform the Fuel Injector Balance Test. Are the fuel injectors OK? | - | Go to Step 8 | Go to Step 15 |
| 14 | - Disconnect the injector test light.
- With a test light connected to ground, probe the ignition feed terminal 1 of the injector harness connector for each cylinder that had misfire.
- Crank the engine.
Does the test light illuminate? | - | Go to Step 16 | Go to Step 18 |
| 15 | Replace any malfunctioning fuel injectors. Is the repair complete? | - | Go to Step 26 | - |
| 16 | Check the affected fuel injector driver circuit at terminals 26, 18, 10, and 2 for an open, short, or short to voltage. Is a problem found? | - | Go to Step 17 | Go to Step 23 |
| 17 | Repair the open or the shorted fuel injector driver circuit. Is the repair complete? | - | Go to Step 26 | - |
| 18 | Repair the open ignition feed circuit between the fuel injector harness connector and the fuel injector connector. Is the repair complete? | - | Go to Step 26 | - |
| 19 | Measure the resistance of the spark plugs that the spark plug tester did not spark. Is the resistance of the spark plug less than the specified value? | 30000 Ω | Go to Step 20 | Go to Step 24 |
| 20 | Inspect the Engine Control Module (ECM) connector and connections. Are the connections OK? | - | Go to Step 21 | Go to Step 22 |
| 21 | Check the affected cylinders ignition control circuit for an open or short and repair as necessary. Is the repair complete? | - | Go to Step 26 | Go to Step 25 |
| 22 | Repair the connector or connections. Is the repair complete? | - | Go to Step 26 | - |
| 23 | - Turn the ignition OFF.
- Replace the ECM.
Is the repair complete? | - | Go to Step 26 | - |
| 24 | Replace the spark plug cable. Is the repair complete? | - | Go to Step 26 | - |
| 25 | Replace the faulty ignition coil. Is the repair complete? | - | Go to Step 26 | Go to Step 23 |
| 26 | - Using the scan tool, clear the DTCs.
- Start the engine and idle at normal operating temperature.
- Operate the vehicle within the conditions for setting this DTC as supported in the text.
Does the scan tool indicate that this diagnostic ran and passed? | - | Go to Step 27 | - |
| 27 | Check if any additional DTCs are set. Are any DTCs displayed that have not been diagnosed? | - | Go to Applicable DTC table | System OK |
Diagnostic Trouble Code (DTC) P0301
Cylinder 1 Misfire Detected
Circuit Description
The Engine Control Module (ECM) monitors the crankshaft and camshaft positions to detect if the engine is misfiring. The ECM looks for a quick drop in crankshaft speed. This test is executed in blocks of 100 engine revolution tests. It may take between one to several tests to store a Diagnostic Trouble Code (DTC) and illuminate the Malfunction Indicator Lamp (MIL). Under light misfire conditions, it may also take more than one trip to set a DTC. Severe misfire will flash the MIL, indicating that catalyst damage is possible.
Conditions for Setting the DTC
- Ignition ON with the engine running.
- No CKP, CMP, MAF, or TP faults exist.
- Misfire detected on single cylinder.
Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will be illuminated as soon as the error occurs.
- The ECM will record operating conditions at the time the diagnostic fail. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The MIL will turn off after three or four consecutive driving cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 consecutive warm up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for 10 seconds.
Diagnostic Aids
An intermittent can also be the result of a defective reluctor wheel. Remove the CKP sensor and inspect the reluctor wheel through the sensor mount hole. Check for porosity and the condition of wheel. If the DTC is intermittent, refer to
"Symptoms Diagnosis" in this section.
DTC P0301 - Cylinder 1 Misfire Detected
| Step | Action | Value(s) | Yes | No |
| 1 | Perform the Diagnostic System Check. Is the system check complete? | - | Go to Step 2 | |
| 2 | - Install a scan tool to the Data Link Connector (DLC).
- Turn the ignition ON, with the engine OFF.
- Request Diagnostic Trouble Codes (DTCs).
Is the DTC P0300 set? | - | Go to Applicable DTC table | Go to Step 3 |
| 3 | - Perform a visual/physical inspection.
- Make any repairs that are necessary.
Is the repair complete? | - | Go to Step 25 | Go to Step 4 |
| 4 | Start the engine and allow it to idle. Are any current misfire counters incrementing? | - | Go to Step 5 | Go to Step 6 |
| 5 | Are all counters equal (within a percentage of each other)? | - | Go to Step 7 | Go to Step 11 |
| 6 | - Turn the ignition ON, with the engine OFF.
- Review the Freeze Frame Data, and note the parameters.
- Operate the vehicle within the Freeze Frame conditions and conditions for setting the DTC as noted.
Are any current misfire counters incrementing? | 410 kPa | Go to Step 5 | |
| 7 | - Turn the engine OFF.
- Install a fuel pressure gauge to the fuel rail.
- Observe the fuel pressure with the engine running.
Is the fuel pressure within the specified value? | 410 kPa | Go to Step 8 | |
| 8 | Check the fuel for contamination. Is the fuel OK? | - | Go to Step 9 | Go to Step 10 |
| 9 | Check for a basic engine problem and repair as necessary. Is the repair complete? | - | Go to Step 25 | - |
| 10 | Replace the contaminated fuel. Is the repair complete? | - | Go to Step 25 | - |
| 11 | - Turn the engine OFF.
- Disconnect the fuel injector harness connector.
- Install a spark tester on cylinder #1.
- Check the engine for a spark.
Is a spark observed? | - | Go to Step 12 | Go to Step 21 |
| 12 | Replace the malfunctioning spark plug. Is the repair complete? | - | Go to Step 25 | Go to Step 13 |
| 13 | - Turn the engine OFF.
- Disconnect the cylinder #1 fuel injector connector from the injector.
- Install an injector test light on the injector harness connector terminal 2.
- Crank the engine and note the test light.
Does the injector test light blink? | - | Go to Step 14 | Go to Step 15 |
| 14 | Perform the Fuel Injector Balance Test. Are the fuel injectors OK? | - | Go to Step 9 | Go to Step 16 |
| 15 | - Disconnect the injector test light.
- With a test light connected to ground, probe the ignition feed terminal 1 of the injector harness connector.
- Crank the engine.
Does the test light illuminate? | - | Go to Step 17 | Go to Step 19 |
| 16 | Replace the malfunctioning fuel injector. Is the repair complete? | - | Go to Step 25 | - |
| 17 | Check the affected fuel injector driver circuit for an open, short to ground or short to voltage. Is a problem found? | - | Go to Step 18 | Go to Step 23 |
| 18 | Repair the open or the shorted fuel injector driver circuit. Is the repair complete? | - | Go to Step 25 | - |
| 19 | Repair the open ignition feed circuit between the fuel injector harness connector and the fuel injector connector. Is the repair complete? | - | Go to Step 25 | - |
| 20 | Inspect the Engine Control Module (ECM) connector and connections. Are the connections OK? | - | Go to Step 21 | Go to Step 22 |
| 21 | Check the affected cylinder ignition control circuit for an open or short and repair as needed. Is the repair complete? | - | Go to Step 25 | Go to Step 24 |
| 22 | Repair the connector or connections. Is the repair complete? | - | Go to Step 25 | - |
| 23 | - Turn the ignition OFF.
- Replace the ECM.
Is the repair complete? | - | Go to Step 25 | - |
| 24 | Replace the faulty ignition coil. Is the repair complete? | - | Go to Step 25 | Go to Step 23 |
| 25 | - Using a scan tool, clear the DTCs.
- Start the engine and idle at normal operating temperature.
- Operate the vehicle within the conditions for setting the DTC as noted.
Does the scan tool indicate that this diagnostic run and pass? | - | Go to Step 26 | Go to Step 2 |
| 26 | Check if any additional DTCs are set. Are any DTCs displayed that have not been diagnosed? | - | Go to Applicable DTC table | System OK |
Diagnostic Trouble Code (DTC) P0302
Cylinder 2 Misfire Detected
Circuit Description
The Engine Control Module (ECM) monitors the crankshaft and camshaft positions to detect if the engine is misfiring. The ECM looks for a quick drop in crankshaft speed. This test is executed in blocks of 100 engine revolution tests. It may take between one to several tests to store a Diagnostic Trouble Code (DTC) and illuminate the Malfunction Indicator Lamp (MIL). Under light misfire conditions, it may also take more than one trip to set a DTC. Severe misfire will flash the MIL, indicating that catalyst damage is possible.
Conditions for Setting the DTC
- Ignition ON with the engine running.
- No CKP, CMP, MAF, or TP faults exist.
- Misfire detected on single cylinder.
Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will be illuminated as soon as the error occurs.
- The ECM will record operating conditions at the time the diagnostic fail. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The MIL will turn off after three or four consecutive driving cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 consecutive warm up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for 10 seconds.
Diagnostic Aids
An intermittent can also be the result of a defective reluctor wheel. Remove the CKP sensor and inspect the reluctor wheel through the sensor mount hole. Check for porosity and the condition of wheel. If the DTC is intermittent, refer to
"Symptoms Diagnosis" in this section.
DTC P0302 - Cylinder 2 Misfire Detected
| Step | Action | Value(s) | Yes | No |
| 1 | Perform the Diagnostic System Check. Is the system check complete? | - | Go to Step 2 | |
| 2 | - Install a scan tool to the Data Link Connector (DLC).
- Turn the ignition ON, with the engine OFF.
- Request Diagnostic Trouble Codes (DTCs).
Is the DTC P0300 set? | - | Go to Applicable DTC table | Go to Step 3 |
| 3 | - Perform a visual/physical inspection.
- Make any repairs that are necessary.
Is the repair complete? | - | Go to Step 25 | Go to Step 4 |
| 4 | Start the engine and allow it to idle. Are any current misfire counters incrementing? | - | Go to Step 5 | Go to Step 6 |
| 5 | Are all counters equal (within a percentage of each other)? | - | Go to Step 7 | Go to Step 11 |
| 6 | - Turn the ignition ON, with the engine OFF.
- Review the Freeze Frame Data, and note the parameters.
- Operate the vehicle within the Freeze Frame conditions and conditions for setting the DTC as noted.
Are any current misfire counters incrementing? | 410 kPa | Go to Step 5 | |
| 7 | - Turn the engine OFF.
- Install a fuel pressure gauge to the fuel rail.
- Observe the fuel pressure with the engine running.
Is the fuel pressure within the specified value? | 410 kPa | Go to Step 8 | |
| 8 | Check the fuel for contamination. Is the fuel OK? | - | Go to Step 9 | Go to Step 10 |
| 9 | Check for a basic engine problem and repair as necessary. Is the repair complete? | - | Go to Step 25 | - |
| 10 | Replace the contaminated fuel. Is the repair complete? | - | Go to Step 25 | - |
| 11 | - Turn the engine OFF.
- Disconnect the fuel injector harness connector.
- Install a spark tester on cylinder #2.
- Check the engine for a spark.
Is a spark observed? | - | Go to Step 12 | Go to Step 21 |
| 12 | Replace the malfunctioning spark plug. Is the repair complete? | - | Go to Step 25 | Go to Step 13 |
| 13 | - Turn the engine OFF.
- Disconnect the cylinder #2 fuel injector connector from the injector.
- Install an injector test light on the injector harness connector terminal 2.
- Crank the engine and note the test light.
Does the injector test light blink? | - | Go to Step 14 | Go to Step 15 |
| 14 | Perform the Fuel Injector Balance Test. Are the fuel injectors OK? | - | Go to Step 9 | Go to Step 16 |
| 15 | - Disconnect the injector test light.
- With a test light connected to ground, probe the ignition feed terminal 1 of the injector harness connector.
- Crank the engine.
Does the test light illuminate? | - | Go to Step 17 | Go to Step 19 |
| 16 | Replace the malfunctioning fuel injector. Is the repair complete? | - | Go to Step 25 | - |
| 17 | Check the affected fuel injector driver circuit for an open, short to ground or short to voltage. Is a problem found? | - | Go to Step 18 | Go to Step 23 |
| 18 | Repair the open or the shorted fuel injector driver circuit. Is the repair complete? | - | Go to Step 25 | - |
| 19 | Repair the open ignition feed circuit between the fuel injector harness connector and the fuel injector connector. Is the repair complete? | - | Go to Step 25 | - |
| 20 | Inspect the Engine Control Module (ECM) connector and connections. Are the connections OK? | - | Go to Step 21 | Go to Step 22 |
| 21 | Check the affected cylinder ignition control circuit for an open or short and repair as needed. Is the repair complete? | - | Go to Step 25 | Go to Step 24 |
| 22 | Repair the connector or connections. Is the repair complete? | - | Go to Step 25 | - |
| 23 | - Turn the ignition OFF.
- Replace the ECM.
Is the repair complete? | - | Go to Step 25 | - |
| 24 | Replace the faulty ignition coil. Is the repair complete? | - | Go to Step 25 | Go to Step 23 |
| 25 | - Using a scan tool, clear the DTCs.
- Start the engine and idle at normal operating temperature.
- Operate the vehicle within the conditions for setting the DTC as noted.
Does the scan tool indicate that this diagnostic run and pass? | - | Go to Step 26 | Go to Step 2 |
| 26 | Check if any additional DTCs are set. Are any DTCs displayed that have not been diagnosed? | - | Go to Applicable DTC table | System OK |
Diagnostic Trouble Code (DTC) P0303
Cylinder 3 Misfire Detected
Circuit Description
The Engine Control Module (ECM) monitors the crankshaft and camshaft positions to detect if the engine is misfiring. The ECM looks for a quick drop in crankshaft speed. This test is executed in blocks of 100 engine revolution tests. It may take between one to several tests to store a Diagnostic Trouble Code (DTC) and illuminate the Malfunction Indicator Lamp (MIL). Under light misfire conditions, it may also take more than one trip to set a DTC. Severe misfire will flash the MIL, indicating that catalyst damage is possible.
Conditions for Setting the DTC
- Ignition ON with the engine running.
- No CKP, CMP, MAF, or TP faults exist.
- Misfire detected on single cylinder.
Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will be illuminated as soon as the error occurs.
- The ECM will record operating conditions at the time the diagnostic fail. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The MIL will turn off after three or four consecutive driving cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 consecutive warm up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for 10 seconds.
Diagnostic Aids
An intermittent can also be the result of a defective reluctor wheel. Remove the CKP sensor and inspect the reluctor wheel through the sensor mount hole. Check for porosity and the condition of wheel. If the DTC is intermittent, refer to
"Symptoms Diagnosis" in this section.
DTC P0303 - Cylinder 3 Misfire Detected
| Step | Action | Value(s) | Yes | No |
| 1 | Perform this Diagnostic System Check. Is the system check complete? | - | Go to Step 2 | |
| 2 | - Install a scan tool to the Data Link Connector (DLC).
- Turn the ignition ON, with the engine OFF.
- Request Diagnostic Trouble Codes (DTCs).
Is the DTC P0300 set? | - | Go to Applicable DTC table | Go to Step 3 |
| 3 | - Perform a visual/physical inspection.
- Make any repairs that are necessary.
Is the repair complete? | - | Go to Step 25 | Go to Step 4 |
| 4 | Start the engine and allow it to idle. Are any current misfire counters incrementing? | - | Go to Step 5 | Go to Step 6 |
| 5 | Are all counters equal (within a percentage of each other)? | - | Go to Step 7 | Go to Step 11 |
| 6 | - Turn the ignition ON, with the engine OFF.
- Review the Freeze Frame Data, and note the parameters.
- Operate the vehicle within the Freeze Frame conditions and conditions for setting the DTC as noted.
Are any current misfire counters incrementing? | 410 kPa | Go to Step 5 | |
| 7 | - Turn the engine OFF.
- Install a fuel pressure gauge to the fuel rail.
- Observe the fuel pressure with the engine running.
Is the fuel pressure within the specified value? | 410 kPa | Go to Step 8 | |
| 8 | Check the fuel for contamination. Is the fuel OK? | - | Go to Step 9 | Go to Step 10 |
| 9 | Check for a basic engine problem and repair as necessary. Is the repair complete? | - | Go to Step 25 | - |
| 10 | Replace the contaminated fuel. Is the repair complete? | - | Go to Step 25 | - |
| 11 | - Turn the engine OFF.
- Disconnect the fuel injector harness connector.
- Install a spark tester on cylinder #3.
- Check the engine for a spark.
Is a spark observed? | - | Go to Step 12 | Go to Step 21 |
| 12 | Replace the malfunctioning spark plug. Is the repair complete? | - | Go to Step 25 | Go to Step 13 |
| 13 | - Turn the engine OFF.
- Disconnect the cylinder #3 fuel injector connector from the injector.
- Install an injector test light on the injector harness connector terminal 2.
- Crank the engine and note the test light.
Does the injector test light blink? | - | Go to Step 14 | Go to Step 15 |
| 14 | Perform the Fuel Injector Balance Test. Are the fuel injectors OK? | - | Go to Step 9 | Go to Step 16 |
| 15 | - Disconnect the injector test light.
- With a test light connected to ground, probe the ignition feed terminal 1 of the injector harness connector.
- Crank the engine.
Does the test light illuminate? | - | Go to Step 17 | Go to Step 19 |
| 16 | Replace the malfunctioning fuel injector. Is the repair complete? | - | Go to Step 25 | - |
| 17 | Check the affected fuel injector driver circuit for an open, short, or short to voltage. Is a problem found? | - | Go to Step 18 | Go to Step 23 |
| 18 | Repair the open or the shorted fuel injector driver circuit. Is the repair complete? | - | Go to Step 25 | - |
| 19 | Repair the open ignition feed circuit between the fuel injector harness connector and the fuel injector connector. Is the repair complete? | - | Go to Step 25 | - |
| 20 | Inspect the Engine Control Module (ECM) connector and connections. Are the connections OK? | - | Go to Step 21 | Go to Step 22 |
| 21 | Check the affected cylinder ignition control circuit for an open or short and repair as needed. Is the repair complete? | - | Go to Step 25 | Go to Step 24 |
| 22 | Repair the connector or connections. Is the repair complete? | - | Go to Step 25 | - |
| 23 | - Turn the ignition OFF.
- Replace the ECM.
Is the repair complete? | - | Go to Step 25 | - |
| 24 | Replace the faulty ignition coil. Is the repair complete? | - | Go to Step 25 | Go to Step 23 |
| 25 | - Using a scan tool, clear the DTCs.
- Start the engine and idle at normal operating temperature.
- Operate the vehicle within the conditions for setting the DTC as noted.
Does the scan tool indicate that this diagnostic run and pass? | - | Go to Step 26 | Go to Step 2 |
| 26 | Check if any additional DTCs are set. Are any DTCs displayed that have not been diagnosed? | - | Go to Applicable DTC table | System OK |
Diagnostic Trouble Code (DTC) P0304
Cylinder 4 Misfire Detected
Circuit Description
The Engine Control Module (ECM) monitors the crankshaft and camshaft positions to detect if the engine is misfiring. The ECM looks for a quick drop in crankshaft speed. This test is executed in blocks of 100 engine revolution tests. It may take between one to several tests to store a Diagnostic Trouble Code (DTC) and illuminate the Malfunction Indicator Lamp (MIL). Under light misfire conditions, it may also take more than one trip to set a DTC. Severe misfire will flash the MIL, indicating that catalyst damage is possible.
Conditions for Setting the DTC
- Ignition ON with the engine running.
- No CKP, CMP, MAF, or TP faults exist.
- Misfire detected on single cylinder.
Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will be illuminated as soon as the error occurs.
- The ECM will record operating conditions at the time the diagnostic fail. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The MIL will turn off after three or four consecutive driving cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 consecutive warm up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for 10 seconds.
Diagnostic Aids
An intermittent can also be the result of a defective reluctor wheel. Remove the CKP sensor and inspect the reluctor wheel through the sensor mount hole. Check for porosity and the condition of wheel. If the DTC is intermittent, refer to
"Symptoms Diagnosis" in this section.
DTC P0304 - Cylinder 4 Misfire Detected
| Step | Action | Value(s) | Yes | No |
| 1 | Perform the Diagnostic System Check. Is the system check complete? | - | Go to Step 2 | |
| 2 | - Install a scan tool to the Data Link Connector (DLC).
- Turn the ignition ON, with the engine OFF.
- Request Diagnostic Trouble Codes (DTCs).
Is the DTC P0300 set? | - | Go to Applicable DTC table | Go to Step 3 |
| 3 | - Perform a visual/physical inspection.
- Make any repairs that are necessary.
Is the repair complete? | - | Go to Step 25 | Go to Step 4 |
| 4 | Start the engine and allow it to idle. Are any current misfire counters incrementing? | - | Go to Step 5 | Go to Step 6 |
| 5 | Are all counters equal (within a percentage of each other)? | - | Go to Step 7 | Go to Step 11 |
| 6 | - Turn the ignition ON, with the engine OFF.
- Review the Freeze Frame Data, and note the parameters.
- Operate the vehicle within the Freeze Frame conditions and conditions for setting the DTC as noted.
Are any current misfire counters incrementing? | 410 kPa | Go to Step 5 | |
| 7 | - Turn the engine OFF.
- Install a fuel pressure gauge to the fuel rail.
- Observe the fuel pressure with the engine running.
Is the fuel pressure within the specified value? | 410 kPa | Go to Step 8 | |
| 8 | Check the fuel for contamination. Is the fuel OK? | - | Go to Step 9 | Go to Step 10 |
| 9 | Check for a basic engine problem and repair as necessary. Is the repair complete? | - | Go to Step 25 | - |
| 10 | Replace the contaminated fuel. Is the repair complete? | - | Go to Step 25 | - |
| 11 | - Turn the engine OFF.
- Disconnect the fuel injector harness connector.
- Install a spark tester on cylinder #4.
- Check the engine for a spark.
Is a spark observed? | - | Go to Step 12 | Go to Step 21 |
| 12 | Replace the malfunctioning spark plug. Is the repair complete? | - | Go to Step 25 | Go to Step 13 |
| 13 | - Turn the engine OFF.
- Disconnect the cylinder #4 fuel injector connector from the injector.
- Install an injector test light on the injector harness connector terminal 2.
- Crank the engine and note the test light.
Does the injector test light blink? | - | Go to Step 14 | Go to Step 15 |
| 14 | Perform the Fuel Injector Balance Test. Are the fuel injectors OK? | - | Go to Step 9 | Go to Step 16 |
| 15 | - Disconnect the injector test light.
- With a test light connected to ground, probe the ignition feed terminal 1 of the injector harness connector.
- Crank the engine.
Does the test light illuminate? | - | Go to Step 17 | Go to Step 19 |
| 16 | Replace the malfunctioning fuel injector. Is the repair complete? | - | Go to Step 25 | - |
| 17 | Check the affected fuel injector driver circuit for an open, short, or short to voltage. Is a problem found? | - | Go to Step 18 | Go to Step 23 |
| 18 | Repair the open or the shorted fuel injector driver circuit. Is the repair complete? | - | Go to Step 25 | - |
| 19 | Repair the open ignition feed circuit between the fuel injector harness connector and the fuel injector connector. Is the repair complete? | - | Go to Step 25 | - |
| 20 | Inspect the Engine Control Module (ECM) connector and connections. Are the connections OK? | - | Go to Step 21 | Go to Step 22 |
| 21 | Check the affected cylinder ignition control circuit for an open or short and repair as needed. Is the repair complete? | - | Go to Step 25 | Go to Step 24 |
| 22 | Repair the connector or connections. Is the repair complete? | - | Go to Step 25 | - |
| 23 | - Turn the ignition OFF.
- Replace the ECM.
Is the repair complete? | - | Go to Step 25 | - |
| 24 | Replace the faulty ignition coil. Is the repair complete? | - | Go to Step 25 | Go to Step 23 |
| 25 | - Using a scan tool, clear the DTCs.
- Start the engine and idle at normal operating temperature.
- Operate the vehicle within the conditions for setting the DTC as noted.
Does the scan tool indicate that this diagnostic run and pass? | - | Go to Step 26 | Go to Step 2 |
| 26 | Check if any additional DTCs are set. Are any DTCs displayed that have not been diagnosed? | - | Go to Applicable DTC table | System OK |
Diagnostic Trouble Code (DTC) P0324
Knock Sensor (KS) Module Performance
Circuit Description
The knock sensor (KS) system enables the engine control module (ECM) to control the ignition timing for the best possible performance while protecting the engine from potentially damaging levels of detonation. The KS produces an AC voltage signal that varies depending on the vibration level during engine operation. The ECM adjusts the spark timing based on the amplitude and the frequency of the KS signal. The ECM learns a minimum KS noise level at idle and uses calibrated values for the rest of the engine speed range. The ECM should monitor a normal KS signal within the noise channel. If the ECM malfunctions in a manner that will not allow proper diagnosis of the KS system, DTC P0324 sets.
Conditions for Running the DTC
- Engine speed is greater than 2200 rpm.
- Engine coolant temperature is greater than 40 °C.
Conditions for Setting the DTC
- Integrator offset value is greater than 0.234 V (Integrator offset -715 mV).
- Integrator gradient is greater than threshold.
- Integrator value difference between end value and start value is less than 3.7 V.
Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will be illuminated after 3 valid driving cycles.
- The ECM will record operating conditions at the time the diagnostic fail. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The MIL will turn off after three or four consecutive driving cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 consecutive warm up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for 10 seconds.
DTC P0324 – Knock Sensor (KS) Module Performance
| Step | Action | Value(s) | Yes | No |
| 1 | Did you perform the Diagnostic System Check? | - | Go to Step 2 | |
| 2 | - Observe the Freeze Frame/Failure Records for this DTC.
- Turn OFF the ignition for 30 seconds.
- Start the engine.
- Operate the vehicle within the Conditions for Setting the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition? | - | Go to Step 3 | |
| 3 | Replace the ECM. Did you complete the replacement? | - | Go to Step 4 | - |
| 4 | - Clear the DTCs with a scan tool.
- Turn OFF the ignition for 30 seconds.
- Start the engine.
- Operate the vehicle within the Conditions for Setting the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition? | - | Go to Step 2 | Go to Step 5 |
| 5 | Check if any additional DTCs are set. Are there any DTCs that have not been diagnosed? | - | Go to Applicable DTC table | System OK |
Diagnostic Trouble Code (DTC) P0327
Knock Sensor (KS) Circuit Low Frequency
Circuit Description
The knock sensor (KS) system enables the engine control module (ECM) to control the ignition timing for the best possible performance while protecting the engine from potentially damaging levels of detonation. The knock sensor (KS) is located on the intake side of the engine block. The KS produces an AC voltage signal that varies depending on the vibration level during engine operation. The ECM adjusts the spark timing based on the amplitude and frequency of the KS signal. The ECM receives the KS signal through a signal circuit. The KS ground is supplied by the ECM through a low reference circuit. The ECM uses the KS signal to calculate the average voltage and then assigns a voltage range value. The ECM should monitor a normal KS signal within the voltage range. If the ECM detects the KS signal outside of the voltage range, or the KS signal is not present, this DTC sets.
Conditions for Setting the DTC
- Nomalized reference level is less than lower limit rpm.
Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will be illuminated after 3 valid driving cycles.
- The ECM will record operating conditions at the time the diagnostic fail. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The MIL will turn off after three or four consecutive driving cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 consecutive warm up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for 10 seconds.
Diagnostic Aids
Check and correct any abnormal engine noise before using the diagnostic table.
Any circuitry that is suspected as causing engine noise complaint should be thoroughly checked for the following conditions:
- Backed-out terminals
- Improper mating
- Broken locks
- Improperly formed
- Damaged terminals
- Poor terminal-to- wire connection
- Physical damage to the wiring harness
DTC P0327 – Knock Sensor (KS) Circuit Low Frequency
| Step | Action | Value(s) | Yes | No |
| 1 | Perform the Diagnostic System Check. Is the system check complete? | - | Go to Step 2 | |
| 2 | - Turn the ignition switch to LOCK.
- Disconnect the ECM connector.
- Using a Digital Volt Meter (DVM), confirm the alternate current (AC) voltage is present between the ECM connector J2 terminal 16 and the ground.
- While tapping on the engine near the knock sensor, check for the presence of the AC voltage.
Does the AC voltage present and change as you tap on the engine? | - | Go to Step 4 | Go to Step 3 |
| 3 | - Replace the Knock Sensor.
- Using the scan tool, clear the Diagnostic Trouble Codes (DTCs).
- Perform the Diagnostic System Check.
Is the repair complete? | - | System OK | - |
| 4 | Check for a torque of the Knock Sensor retaining bolt. Is the torque between the specified values? | 18~20 N•m (13~15 lb-ft) | Go to Step 6 | Go to Step 5 |
| 5 | Tighten the Knock Sensor Retaining Bolt to the specified torque. Is the repair complete? | 18~20 N•m (13~15 lb-ft) | System OK | - |
| 6 | - Turn the ignition switch to LOCK.
- Disconnect the knock sensor connector.
- Disconnect the ECM connector.
- Check for an open or short to ground in the wire between the knock sensor connector terminal 3, 2, 1 and the ECM connector J2 terminal 16, 8, ground, respectively.
Is the problem found? | - | Go to Step 7 | Go to Step 8 |
| 7 | - Repair the wire or the connector terminal as needed.
- Using the scan tool, clear the Diagnostic Trouble Codes (DTCs).
- Perform the Diagnostic System Check.
Is the repair complete? | - | System OK | - |
| 8 | - Turn the ignition switch to LOCK.
- Replace the ECM.
- Perform the Diagnostic System Check.
Is the repair complete? | - | System OK | - |
Diagnostic Trouble Code (DTC) P0328
Knock Sensor (KS) Circuit High Frequency
Circuit Description
The knock sensor (KS) system enables the engine control module (ECM) to control the ignition timing for the best possible performance while protecting the engine from potentially damaging levels of detonation. The knock sensor (KS) is located on the intake side of the engine block. The KS produces an AC voltage signal that varies depending on the vibration level during engine operation. The ECM adjusts the spark timing based on the amplitude and frequency of the KS signal. The ECM receives the KS signal through a signal circuit. The KS ground is supplied by the ECM through a low reference circuit. The ECM uses the KS signal to calculate the average voltage and then assigns a voltage range value. The ECM should monitor a normal KS signal within the voltage range. If the ECM detects the KS signal outside of the voltage range, or the KS signal is not present, this DTC sets.
Conditions for Setting the DTC
- Nomalized reference level is greater than upper limit rpm.
- Engine coolant temperature is greater than 65.24°C.
- Mass air flow is greater than 251 mg/stk.
- Engine speed is greater than 2496 rpm.
- KS signal is less than 0.299V or the difference between a original signal and filtering value is less than thresholds.
Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will be illuminated after 3 valid driving cycles.
- The ECM will record operating conditions at the time the diagnostic fail. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The MIL will turn off after three or four consecutive driving cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 consecutive warm up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for 10 seconds.
Diagnostic Aids
Check and correct any abnormal engine noise before using the diagnostic table.
Any circuitry that is suspected as causing engine noise complaint should be thoroughly checked for the following conditions:
- Backed-out terminals
- Improper mating
- Broken locks
- Improperly formed
- Damaged terminals
- Poor terminal-to- wire connection
- Physical damage to the wiring harness
DTC P0328 – Knock Sensor (KS) Circuit High Frequency
| Step | Action | Value(s) | Yes | No |
| 1 | Perform the Diagnostic System Check. Is the system check complete? | - | Go to Step 2 | |
| 2 | - Turn the ignition switch to LOCK.
- Disconnect the ECM connector.
- Using a Digital Volt Meter (DVM), confirm the alternate current (AC) voltage is present between the ECM connector J2 terminal 16 and the ground.
- While tapping on the engine near the knock sensor, check for the presence of the AC voltage.
Does the AC voltage present and change as you tap on the engine? | - | Go to Step 4 | Go to Step 3 |
| 3 | - Replace the Knock Sensor.
- Using the scan tool, clear the Diagnostic Trouble Codes (DTCs).
- Perform the Diagnostic System Check.
Is the repair complete? | - | System OK | - |
| 4 | Check for a torque of the Knock Sensor retaining bolt. Is the torque between the specified values? | 18~20 N•m (13~15 lb-ft) | Go to Step 6 | Go to Step 5 |
| 5 | Tighten the Knock Sensor Retaining Bolt to the specified torque. Is the repair complete? | 18~20 N•m (13~15 lb-ft) | System OK | - |
| 6 | - Turn the ignition switch to LOCK.
- Disconnect the knock sensor connector.
- Disconnect the ECM connector.
- Check for a short to battery in the wire between the knock sensor connector terminal 3, 2, 1 and the ECM connector J2 terminal 16, 8, ground, respectively.
Is the problem found? | - | Go to Step 7 | Go to Step 8 |
| 7 | - Repair the wire or the connector terminal as needed.
- Using the scan tool, clear the Diagnostic Trouble Codes (DTCs).
- Perform the Diagnostic System Check.
Is the repair complete? | - | System OK | - |
| 8 | - Turn the ignition switch to LOCK.
- Replace the ECM.
- Perform the Diagnostic System Check.
Is the repair complete? | - | System OK | - |
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