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Home >> Suzuki >> 2004 >> Swift + >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - 1.6L (L91) (DTC P0300 To DTC P0488) >> Diagnostic Information & Procedures >> DTC P0300 >> Test Description
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Test Description

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

  1. 2:  This step determines if there is a current misfire condition. The scan tool will display increasing counts in the Total Misfire Current Counter parameter if a misfire is occurring.
  1. 3:  If the Total Misfire Current Counter parameter is incrementing, but the engine is NOT misfiring, this could be caused by an excessive vibration from other sources than the engine.
  1. 4:  If the actual CKP variation values are not within the learned values, the Total Misfire Current Counter parameter may increment.
DTC P0300

Step Action Values Yes No
1 Did you perform the Diagnostic System Check - Engine Controls? - Go to Step 2  Go to Diagnostic System Check - Engine Controls
2 
IMPORTANT: A misfire may only occur when the engine is under a load. An engine load may be necessary to verify the condition.
  1. Turn ON the ignition, with the engine OFF.
  2. Clear the DTCs with a scan tool.
  3. Start the engine.
  4. Monitor the Misfire Current Cylinder counter parameters with a scan tool.
Are any of the Misfire Current Cylinder counters incrementing?		 - Go to Step 4  Go to Step 3 
3 
  1. Observe the Freeze Frame/Failure Records for this DTC.
  2. Turn the ignition OFF 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 4  Go to Diagnostic Aids
4  Is the engine misfiring? - Go to Step 5  Go to CKP System Variation Learn Procedure
5 Are DTCs P0201, P0202, P0203, P0204, P0315, P0336, P0337, P0351, or P0352 set? - Go to Diagnostic Trouble Code (DTC) List Go to Step 6 
6 Is there an abnormal engine noise? - Go to Symptoms - Engine Mechanical in Engine Mechanical - 1.6L (L91) Go to Step 7 
7 Inspect the following components:
Did you find and correct the condition?		 - Go to Step 20  Go to Step 8 
8
    IMPORTANT: An erratic or inconsistent spark is considered a no spark.
  1. Turn OFF the ignition.
  2. Disconnect the spark plug wire from the spark plug that corresponds to the Misfire Current Cylinder counter parameters that were incrementing. Refer to Spark Plug Wire Replacement .
  3. Install the J 26792  Spark Tester to the boot of the spark plug and a good ground.
  4. Start the engine.
Does the spark jump the tester gap?		   Go to Step 10  Go to Step 9 
9
  1. Remove the spark plug wire for the affected cylinders. Refer to Spark Plug Wire Replacement .
  2. Inspect the spark plug wire. Refer to SPARK PLUG WIRE INSPECTION .
  3. Measure the resistance of the spark plug wire with a DMM.
Is the spark plug wire resistance less than the specified value?		 1,000 Ω per 30 cm (per ft) Go to Electronic Ignition (EI) System Diagnosis Go to Step 19 
10
  1. Remove the spark plug from the cylinders 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 11  Go to Step 12 
11
  1. Exchange the suspected spark plug with another cylinder that is operating correctly. 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 18  Go to Step 15 
12 Is the spark plug oil or coolant fouled? - Go to Symptoms - Engine Mechanical in Engine Mechanical - 1.6L (L91) Go to Step 13 
13 Is the spark plug gas fouled? - Go to Step 16  Go to Step 14 
14 Did the spark plug show any signs of being cracked, worn, or improperly gapped? - Go to Step 17  Go to Step 15 
15 Perform the fuel injector coil test. Refer to Fuel Injector Coil Test .
Did you find and correct the condition?		 - Go to Step 20  Go to Symptoms - Engine Mechanical in Engine Mechanical - 1.6L (L91)
16 Perform the fuel system diagnosis. Refer to Fuel System Diagnosis .
Did you find and correct the condition?		 - Go to Step 20  Go to Symptoms - Engine Mechanical in Engine Mechanical - 1.6L (L91)
17 Replace or gap the spark plug. Refer to Spark Plug Replacement .
Did you complete the action?		 - Go to Step 20  -
18 Replace the spark plug. Refer to Spark Plug Replacement .
Did you complete the replacement?		 - Go to Step 20  -
19 Replace the spark plug wires. Refer to Spark Plug Wire Replacement .
Did you complete the replacement?		 - Go to Step 20  -
20 Was the customer concern the malfunction indicator lamp (MIL) flashing? - Go to Step 21  Go to Step 22 
21 Operate the vehicle within the Conditions for Running the DTC P0420 as specified in the supporting text. Refer to DTC P0420 .
Did the DTC run and pass?		 - Go to Step 22  Go to DTC P0420 
22
  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 23 
23 Observe the Capture Info with a scan tool.
Are there any DTCs that have not been diagnosed?		 - Go to Diagnostic Trouble Code (DTC) List System OK
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