Lack of Power, Sluggish or Spongy Symptom
Step
| Action
| Value(s)
| Yes
| No
|
Definition: The engine
delivers less than the expected power. There is little or no increase in the
speed when the accelerator pedal is pushed down part way.
|
1
| Did you perform the On-Board Diagnostic (OBD) System Check?
| --
|
Go to Step
2
| Go to the
Powertrain On Board Diagnostic (OBD) System Check
|
2
|
- Perform a bulletin search.
- If a bulletin that addresses the symptom is present, correct the
condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom?
| --
|
Go to Step 17
|
Go to Step 3
|
3
| Did you perform a visual/physical check?
| --
|
Go to Step 4
| Go to
Symptoms
for the
Visual /Physical Check
|
4
|
- Remove and check the air filter element for dirt or for a restriction.
- Replace the air filter element if necessary.
Was a repair required?
| --
|
Go to Step 17
|
Go to Step 5
|
5
| Check
the Intake Plenum Switchover Valve and the Intake Resonance Switchover Valve
for a proper operation. Refer to
DTC P1112 Intake Plenum Switchover Solenoid Control Circuit
and
DTC P1113 Intake Resonance Switchover Solenoid Control Circuit
.
Was a problem found and corrected?
| --
|
Go to Step 17
|
Go to Step 6
|
6
|
- Check for low fuel pressure. Refer to
Fuel System Diagnosis
.
- If a problem is present, repair as necessary.
Was a problem found?
| --
|
Go to Step 17
|
Go to Step 7
|
7
|
- Use a J 39383-A in order to check for water or alcohol
contaminated fuel.
- If a problem is present, repair as necessary.
Was a problem found?
| --
|
Go to Step 17
|
Go to Step 8
|
8
|
- Use a scan tool in order to monitor the Knock Retard for an excessive
spark retard activity.
- If a problem is present, repair as necessary.
Was a problem found?
| --
|
Go to Step 17
|
Go to Step 9
|
9
|
- Check for a proper ignition coil output voltage with spark tester J 26792
(ST 125) by performing
the following procedure:
1.1. | Clip the spark tester J 26792
to engine ground. |
1.2. | Connect one end of a spark plug wire to the spark tester J 26792
. Leave the other end of
the spark plug wire connected to the coil that is being tested. |
1.3. | Disconnect the spark plug wire from the other spark plug on the
same coil being tested. Ground the wire. |
1.4. | Crank the engine while observing the spark tester J 26792
. Look for a blue spark. |
1.5. | Repeat the above steps for each coil. |
- If an adequate spark is not present at all of the coils, repair
as necessary.
Was a problem found?
| --
|
Go to Step 17
|
Go to Step 10
|
10
|
- Remove the spark plugs. Check for the following conditions:
• | Carbon tracking on the insulator |
Notice: Determine the cause of the oil or gas fouled spark plugs in order to
avoid damage to the new spark plugs.
- If a problem is present, repair as necessary.
Was a problem found?
| --
|
Go to Step 17
|
Go to Step 11
|
11
|
- Check the ignition coils for cracks or carbon tracking.
- If a problem is present, repair as necessary.
Was a problem found?
| --
|
Go to Step 17
|
Go to Step 12
|
12
|
- Check the ECMPCM grounds for being clean, tight and in the proper
locations.
- If a problem is present, repair as necessary.
Was a problem found?
| --
|
Go to Step 17
|
Go to Step
13
|
13
|
- Check the exhaust system for a possible restriction:
• | Inspect the exhaust system for any damaged or collapsed pipes. |
• | Inspect the muffler for heat distress or a possible internal failure. |
- If a problem is present, repair as necessary.
Was a problem found?
| --
|
Go to Step 17
|
Go to Step
14
|
14
|
- Check the Torque Converter Clutch (TCC) for a proper operation.
Refer to
Transmission Diagnosis
- If a problem is present, repair as necessary.
Was a problem found?
| --
|
Go to Step 17
|
Go to Step 15
|
15
|
- Check for the following Engine Mechanical problems. Refer to Engine Mechanical:
• | A hydraulic valve lifter problem |
• | Leaking cylinder head gaskets |
• | Worn or incorrect camshaft |
- If a problem is present, repair as necessary.
Was a problem found?
| --
|
Go to Step 17
|
Go to Step 16
|
16
|
- Review all of the diagnostic procedures within this table.
- When all of the procedures have been completed and no malfunctions
are present, review/inspect the following items:
• | All of the connections within a suspected circuit and/or system |
- If a problem is present, repair as necessary.
Was a problem found?
| --
|
Go to Step 17
|
Go to Step 3
|
17
| Operate
the vehicle under the same conditions (as closely as possible) as when the
original symptom occurred.
Is the original symptom still present?
| --
|
Go to Step 3
| The repair is complete. If
another driveability symptom exists, refer to
Symptoms
.
|