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For 1990-2009 cars only

Surges and/or Chuggles Symptom

Step

Action

Value(s)

Yes

No

Definition: The definition of this symptom is the engine power variation under a steady throttle or cruise. The sensation of the ride feels like the vehicle speeds up and slows down with no change in the accelerator pedal.

1

Did you perform the Powertrain On-Board Diagnostic (OBD) System Check performed?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

  1. Perform a bulletin search.
  2. If a bulletin that addresses the symptom is present, correct the condition as instructed in the bulletin.

Did you find a bulletin that addresses the symptom?

--

Go to Step 18

Go to Step 3

3

Perform the careful visual/physical checks as described at the start of Symptoms section.

Did you perform the visual/physical check?

--

Go to Step 4

Go to Important Preliminary Checks

4

  1. Check the Oxygen Sensor (O2S 1). The Oxygen Sensor (O2S 1) should respond quickly to the different throttle position.
  2. If the O2S 1 does not respond quickly, check the O2S 1 for silicon or other contaminants from fuel or from the use of improper RTV sealant. The sensor may have a white powdery coating. Silicon contamination causes in a high but false O2S 1 signal voltage (rich exhaust indication). The PCM will then reduce the amount of fuel delivered to the engine, causing a severe driveability problem. For more information, refer to Powertrain Control Module Inputs Diagnosis .
  3. If a problem is present, repair the problem as necessary.

Was a repair necessary?

--

Go to Step 18

Go to Step 5

5

  1. Check the fuel pressure. Refer to Fuel System Diagnosis .
  2. If a problem is present, repair the problem as necessary.

Was a repair necessary?

--

Go to Step 18

Go to Step 6

6

Monitor the Long Term Fuel Trim on the scan tool.

Is the Long Term Fuel Trim significantly in the negative range (Rich condition)?

--

Go to Step 7

Go to Step 8

7

  1. Check the items that can cause the engine to run rich. Refer to DTC P0172 Fuel Trim System Rich .
  2. If a problem is present, repair the problem as necessary.

Was a repair necessary?

--

Go to Step 8

Go to Step 18

8

  1. Check the items that can cause the engine to run lean. Refer to DTC P0171 Fuel Trim System Lean .
  2. If a problem is found, repair as necessary.

Was a problem found?

--

Go to Step 9

Go to Step 18

9

  1. Check for proper ignition voltage output with spark plug jumper wires J 36012 and spark tester J  26792.
  2. If a problem is present, repair the problem as necessary.

Was a repair necessary?

--

Go to Step 18

Go to Step 10

10

  1. Check the ignition coils for cracks or carbon tracking.
  2. If a problem is present, repair as necessary.

Was a repair necessary?

--

Go to Step 18

Go to Step 11

11

  1. Check the ignition coil secondary resistance.
  2. Replace any coil(s) which are not within the specified values.

Did any coil(s) require a replacement?

5000-8000 ohms (5 Kohms-8 Kohms)

Go to Step 18

Go to Step 12

12

    Notice: If spark plugs are gas or oil fouled, determime the cause of the fouling before replacing the spark plugs in order to avoid damage to the new spark plugs.

  1. Remove the spark plugs.
  2. Check for the following conditions:
  3. • Wet plugs
    • Cracks
    • Wear
    • Improper gap
    • Burned electrodes
    • Heavy deposits.
  4. If a problem is present, repair the problem as necessary.

Was a repair necessary?

--

Go to Step 18

Go to Step 13

13

  1. Check the injector connections.
  2. If any of the injectors connectors are connected to an incorrect cylinder, correct the problem as necessary.

Was a repair necessary?

--

Go to Step 18

Go to Step 14

14

  1. Check the PCM grounds for being clean, tight and in the proper locations. Refer to the PCM wiring diagrams in the Electrical Diagnosis portion of the service manual.
  2. If a problem is present, repair the problem as necessary.

Was a repair necessary?

--

Go to Step 18

Go to Step 15

15

  1. Visually/physically check the vacuum hoses for splits, kinks, and proper connections and routing as shown on Vehicle Emission Control Information label.
  2. If a problem is present, repair the problem as necessary.

Was a repair necessary?

--

Go to Step 18

Go to Step 16

16

  1. Check for a proper generator voltage output.
  2. The voltage should be between the specified values.

Is the voltage between the specified values?

11-16 V

Go to Step 17

Go to Powertrain Control Module Controlled Generator Diagnosis

17

  1. Review all of the diagnostic procedures within this table.
  2. If you have completed all of the procedures and no malfunctions are present, review/inspect the following items:
  3. • Visual/physical inspection
    • Scan tool data
    • All electrical connections within a suspected circuit and/or system
  4. If a problem is present, repair the problem as necessary.

Was a repair necessary?

--

Go to Step 18

--

18

Operate the vehicle within the conditions under which the original symptom was observed.

Does the system now operate properly?

--

System OK

Go to Step 2