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Home >> Chevrolet >> 2006 >> HHR LS, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - 2.2L - DTC P0136 To P0446 >> DTC P0300-P0304 >> Test Description
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Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. 2:  If the actual CKP variation values are not within the learned values, the misfire counters may increment.
  2. 3:  P0300, P0340, and P0341 may all be set by similar conditions.
DTC P0300

Step Action Values Yes No
1 Did you perform the Diagnostic System Check - Vehicle? - Go to Step 2  Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
2 
  1. Start the engine.
  2. Allow the engine to idle or operate within the conditions listed in the Freeze Frame/Failure Records.
  3. Monitor all of the Misfire counters with the scan tool.
Are any of the Misfire Current counters incrementing?		 - Go to Step 3  Go to Intermittent Conditions
3  Are any DTCs other than P0340 or P0341 set? - Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information Go to Step 4 
4 Can any abnormal engine noise be heard? - Go to Symptoms - Engine Mechanical Go to Step 5 
5 Observe the Misfire History Cyl# parameter with a scan tool.
Does more than one cylinder indicate a large count value for the Misfire History Cyl# parameter?		 - Go to Step 6  Go to Step 8 
6 Are the Misfire History Cyl# counts indicated for companion cylinders 1/4 or 2/3? - Go to Step 8  Go to Step 7 
7 Inspect the following components:
Did you find and correct the condition?		 - Go to Step 17  Go to Step 8 
8
  1. Turn OFF the ignition.
  2. Remove the fuel pump relay. Refer to Relay Replacement (Within an Electrical Center) or Relay Replacement (Attached to Wire Harness) in Wiring Systems.
  3. Remove the ignition coil housing assembly, keeping the ignition control (IC) module assembly connected to the harness connector. Refer to Ignition Coil Housing Replacement .
    4. IMPORTANT: Not grounding the IC module housing may cause an erratic spark.
  4. Connect a jumper wire between the top of the IC module and a good ground.
  5. Install the J 36012-A  Ignition System Diagnosis Harness. See Special Tools .
  6. Install a J 26792  Spark Tester on the #1 spark plug jumper wire. See Special Tools .
  7. Ground the #4 spark plug jumper wire. The #4 wire is the companion to #1.
  8. Crank the engine with the remaining spark plug wires connected.
  9. Repeat the above steps by installing the spark tester on #4 and grounding #1. Do the same for the #2 and the #3 spark plugs. Ensure the companion wire is grounded.
Does the spark tester spark on all cylinders?		 - Go to Step 9  Go to Electronic Ignition (EI) System Diagnosis (Without Special Tool) or Electronic Ignition (EI) System Diagnosis (With Special Tool)
9
  1. Remove the spark plug from the cylinder that indicated a misfire. Refer to Spark Plug Replacement .
  2. Inspect the spark plug. Refer to Spark Plug Inspection .
Does the spark plug appear to be OK?		 - Go to Step 10  Go to Step 11 
10
  1. Exchange the suspected spark plug with another cylinder that is operating properly. Refer to Spark Plug Replacement .
  2. Operate the vehicle under the same conditions that the misfire occurred.
Did the misfire move with the spark plug?		 - Go to Step 17  Go to Step 14 
11 Is the spark plug oil or coolant fouled? - Go to Symptoms - Engine Mechanical Go to Step 12 
12 Is the spark plug gas fouled? - Go to Step 15  Go to Step 13 
13 Did the spark plug show any signs of being cracked, worn, or improperly gapped? - Go to Step 16  Go to Step 14 
14 Perform the fuel injector coil test. Refer to Fuel Injector Coil Test .
Did you find and correct the condition?		 - Go to Step 18  Go to Symptoms - Engine Mechanical
15 Perform the fuel system diagnosis. Refer to Fuel System Diagnosis .
Did you find and correct the condition?		 - Go to Step 18  Go to Symptoms - Engine Mechanical
16 Replace or gap the spark plug. Refer to Spark Plug Replacement .
Did you complete the action?		 - Go to Step 18  -
17 Replace the faulty spark plug. Refer to Spark Plug Replacement .
Did you complete the replacement?		 - Go to Step 18  -
18 Was the customer concern the malfunction indicator lamp (MIL) flashing? - Go to Step 19  Go to Step 20 
19
  1. Operate the vehicle at the specified value for 4 minutes.
  2. Operate the vehicle within the Conditions for Running the DTC P0420, as specified in the supporting text. Refer to DTC P0420 .
Does the DTC run and pass?		 2,500 RPM Go to Step 20  Go to DTC P0420 
20
  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 Running 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 21 
21 Observe the Capture Info with a scan tool.
Are there any DTCs that have not been diagnosed?		 - Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information System OK
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