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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

Conditions for Setting the DTC

Action Taken When the DTC Sets

Conditions for Clearing the MIL/DTC

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
Go to "Diagnostic System Check"
2
  1. Perform a visual/physical inspection.
  2. 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
  1. Turn the ignition ON, with the engine OFF.
  2. Review the Freeze Frame data, and note the parameters.
  3. 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
Go to "Diagnostic Aids"
6
  1. Turn the engine OFF.
  2. Install a fuel pressure gauge to the fuel rail.
  3. Observe the fuel pressure with the engine running.
Is the fuel pressure within the specified value?
410 kPa
Go to Step 7
Go to "Fuel System Diagnosis"
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
  1. Turn the engine OFF.
  2. Disconnect the fuel injector harness connector.
  3. 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
  1. Turn the engine OFF.
  2. Disconnect the fuel injector connectors from the injectors.
  3. Install an injector test light on the injector harness connector for the cylinders that had misfired.
  4. 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
  1. Disconnect the injector test light.
  2. With a test light connected to ground, probe the ignition feed terminal 1 of the injector harness connector for each cylinder that had misfire.
  3. 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
  1. Turn the ignition OFF.
  2. 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
  1. Using the scan tool, clear the DTCs.
  2. Start the engine and idle at normal operating temperature.
  3. 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

Action Taken When the DTC Sets

Conditions for Clearing the MIL/DTC

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
Go to "Diagnostic System Check"
2
  1. Install a scan tool to the Data Link Connector (DLC).
  2. Turn the ignition ON, with the engine OFF.
  3. Request Diagnostic Trouble Codes (DTCs).
Is the DTC P0300 set?
-
Go to Applicable DTC table
Go to Step 3
3
  1. Perform a visual/physical inspection.
  2. 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
  1. Turn the ignition ON, with the engine OFF.
  2. Review the Freeze Frame Data, and note the parameters.
  3. 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
Go to "Diagnostic Aids"
7
  1. Turn the engine OFF.
  2. Install a fuel pressure gauge to the fuel rail.
  3. Observe the fuel pressure with the engine running.
Is the fuel pressure within the specified value?
410 kPa
Go to Step 8
Go to "Fuel System Diagnosis"
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
  1. Turn the engine OFF.
  2. Disconnect the fuel injector harness connector.
  3. Install a spark tester on cylinder #1.
  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
  1. Turn the engine OFF.
  2. Disconnect the cylinder #1 fuel injector connector from the injector.
  3. Install an injector test light on the injector harness connector terminal 2.
  4. 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
  1. Disconnect the injector test light.
  2. With a test light connected to ground, probe the ignition feed terminal 1 of the injector harness connector.
  3. 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
  1. Turn the ignition OFF.
  2. 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
  1. Using a scan tool, clear the DTCs.
  2. Start the engine and idle at normal operating temperature.
  3. 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

Action Taken When the DTC Sets

Conditions for Clearing the MIL/DTC

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
Go to "Diagnostic System Check"
2
  1. Install a scan tool to the Data Link Connector (DLC).
  2. Turn the ignition ON, with the engine OFF.
  3. Request Diagnostic Trouble Codes (DTCs).
Is the DTC P0300 set?
-
Go to Applicable DTC table
Go to Step 3
3
  1. Perform a visual/physical inspection.
  2. 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
  1. Turn the ignition ON, with the engine OFF.
  2. Review the Freeze Frame Data, and note the parameters.
  3. 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
Go to "Diagnostic Aids"
7
  1. Turn the engine OFF.
  2. Install a fuel pressure gauge to the fuel rail.
  3. Observe the fuel pressure with the engine running.
Is the fuel pressure within the specified value?
410 kPa
Go to Step 8
Go to "Fuel System Diagnosis"
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
  1. Turn the engine OFF.
  2. Disconnect the fuel injector harness connector.
  3. Install a spark tester on cylinder #2.
  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
  1. Turn the engine OFF.
  2. Disconnect the cylinder #2 fuel injector connector from the injector.
  3. Install an injector test light on the injector harness connector terminal 2.
  4. 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
  1. Disconnect the injector test light.
  2. With a test light connected to ground, probe the ignition feed terminal 1 of the injector harness connector.
  3. 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
  1. Turn the ignition OFF.
  2. 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
  1. Using a scan tool, clear the DTCs.
  2. Start the engine and idle at normal operating temperature.
  3. 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

Action Taken When the DTC Sets

Conditions for Clearing the MIL/DTC

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
Go to "Diagnostic System Check"
2
  1. Install a scan tool to the Data Link Connector (DLC).
  2. Turn the ignition ON, with the engine OFF.
  3. Request Diagnostic Trouble Codes (DTCs).
Is the DTC P0300 set?
-
Go to Applicable DTC table
Go to Step 3
3
  1. Perform a visual/physical inspection.
  2. 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
  1. Turn the ignition ON, with the engine OFF.
  2. Review the Freeze Frame Data, and note the parameters.
  3. 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
Go to "Diagnostic Aids"
7
  1. Turn the engine OFF.
  2. Install a fuel pressure gauge to the fuel rail.
  3. Observe the fuel pressure with the engine running.
Is the fuel pressure within the specified value?
410 kPa
Go to Step 8
Go to "Fuel System Diagnosis"
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
  1. Turn the engine OFF.
  2. Disconnect the fuel injector harness connector.
  3. Install a spark tester on cylinder #3.
  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
  1. Turn the engine OFF.
  2. Disconnect the cylinder #3 fuel injector connector from the injector.
  3. Install an injector test light on the injector harness connector terminal 2.
  4. 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
  1. Disconnect the injector test light.
  2. With a test light connected to ground, probe the ignition feed terminal 1 of the injector harness connector.
  3. 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
  1. Turn the ignition OFF.
  2. 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
  1. Using a scan tool, clear the DTCs.
  2. Start the engine and idle at normal operating temperature.
  3. 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

Action Taken When the DTC Sets

Conditions for Clearing the MIL/DTC

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
Go to "Diagnostic System Check"
2
  1. Install a scan tool to the Data Link Connector (DLC).
  2. Turn the ignition ON, with the engine OFF.
  3. Request Diagnostic Trouble Codes (DTCs).
Is the DTC P0300 set?
-
Go to Applicable DTC table
Go to Step 3
3
  1. Perform a visual/physical inspection.
  2. 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
  1. Turn the ignition ON, with the engine OFF.
  2. Review the Freeze Frame Data, and note the parameters.
  3. 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
Go to "Diagnostic Aids"
7
  1. Turn the engine OFF.
  2. Install a fuel pressure gauge to the fuel rail.
  3. Observe the fuel pressure with the engine running.
Is the fuel pressure within the specified value?
410 kPa
Go to Step 8
Go to "Fuel System Diagnosis"
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
  1. Turn the engine OFF.
  2. Disconnect the fuel injector harness connector.
  3. Install a spark tester on cylinder #4.
  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
  1. Turn the engine OFF.
  2. Disconnect the cylinder #4 fuel injector connector from the injector.
  3. Install an injector test light on the injector harness connector terminal 2.
  4. 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
  1. Disconnect the injector test light.
  2. With a test light connected to ground, probe the ignition feed terminal 1 of the injector harness connector.
  3. 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
  1. Turn the ignition OFF.
  2. 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
  1. Using a scan tool, clear the DTCs.
  2. Start the engine and idle at normal operating temperature.
  3. 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

Conditions for Setting the DTC

Action Taken When the DTC Sets

Conditions for Clearing the MIL/DTC

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
Go to "Diagnostic System Check"
2
  1. Observe the Freeze Frame/Failure Records for this DTC.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. 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
Go to "Intermittents"
3
Replace the ECM.
Did you complete the replacement?
-
Go to Step 4
-
4
  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. 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

Action Taken When the DTC Sets

Conditions for Clearing the MIL/DTC

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:

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
Go to "Diagnostic System Check"
2
  1. Turn the ignition switch to LOCK.
  2. Disconnect the ECM connector.
  3. Using a Digital Volt Meter (DVM), confirm the alternate current (AC) voltage is present between the ECM connector J2 terminal 16 and the ground.
  4. 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
  1. Replace the Knock Sensor.
  2. Using the scan tool, clear the Diagnostic Trouble Codes (DTCs).
  3. 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
  1. Turn the ignition switch to LOCK.
  2. Disconnect the knock sensor connector.
  3. Disconnect the ECM connector.
  4. 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
  1. Repair the wire or the connector terminal as needed.
  2. Using the scan tool, clear the Diagnostic Trouble Codes (DTCs).
  3. Perform the Diagnostic System Check.
Is the repair complete?
-
System OK
-
8
  1. Turn the ignition switch to LOCK.
  2. Replace the ECM.
  3. 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

Action Taken When the DTC Sets

Conditions for Clearing the MIL/DTC

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:

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
Go to "Diagnostic System Check"
2
  1. Turn the ignition switch to LOCK.
  2. Disconnect the ECM connector.
  3. Using a Digital Volt Meter (DVM), confirm the alternate current (AC) voltage is present between the ECM connector J2 terminal 16 and the ground.
  4. 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
  1. Replace the Knock Sensor.
  2. Using the scan tool, clear the Diagnostic Trouble Codes (DTCs).
  3. 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
  1. Turn the ignition switch to LOCK.
  2. Disconnect the knock sensor connector.
  3. Disconnect the ECM connector.
  4. 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
  1. Repair the wire or the connector terminal as needed.
  2. Using the scan tool, clear the Diagnostic Trouble Codes (DTCs).
  3. Perform the Diagnostic System Check.
Is the repair complete?
-
System OK
-
8
  1. Turn the ignition switch to LOCK.
  2. Replace the ECM.
  3. Perform the Diagnostic System Check.
Is the repair complete?
-
System OK
-


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