Lack of Power

Definition: Engine delivers less than expected power. Little or no increase in speed when accelerator pedal is pushed down part-way.

1. Was the "On-Board Diagnostic (OBD) System Check" performed?

[YES] Go to Step 2.
[NO] Go to OBD System Check. Initial Inspection

2. a. Perform a bulletin search.
b. If a bulletin that addresses the symptom is found, correct the condition as instructed in the bulletin.
c. Was a bulletin found that addresses the symptom?

[YES] Verify repair.
[NO] Go to Step 3.

3. Was a visual/physical check performed?

[YES] Go to Step 4.
[NO] Go to Visual/Physical Check. Visual/Physical Check

4. a. Remove and check the air filter element for dirt or restriction.
b. Replace the air filter element if necessary.
c. Was a repair required?

[YES] Verify repair.
[NO] Go to Step 5.

5. a. Check for proper ignition voltage output with the spark tester J 26792.
b. Was a problem found?

[YES] Verify repair.
[NO] Go to Step 6.

6. a. Remove the spark plugs and check gas or oil fouling, cracks, wear, improper gap, burned electrodes, heavy deposits or improper heat range.
b. If spark plugs are fouled, the cause of fouling must be determined before replacing the spark plug.
c. Was a problem found?

[YES] Verify repair.
[NO] Go to Step 7.

7. a. Remove the distributor cap and check for cracks or carbon tracking.
b. Was a problem found?

[YES] Verify repair.
[NO] Go to Step 8.
8. a. Check the fuel pressure.
b. Was a problem found?

[YES] Verify repair.
[NO] Go to Step9.

9. a. Check for water or alcohol contaminated fuel.
b. Was a problem found?

[YES] Verify repair.
[NO] Go to Step 10.

10. a. Check the Powertrain Control Module (PCM) grounds to verify that they are clean and tight.
b. Was a problem found?

[YES] Verify repair.
[NO] Go to Step 11.

11. a. Check the exhaust system for a possible restriction:
- Damaged or collapsed pipes.
- Internal muffler failure.
- Measure backpressure and determine if the catalytic converter is plugged.
b. Was a problem found?

[YES] Verify repair.
[NO] Go to Step 12.

12. a. Check for the following engine mechanical problems.
- Low compression.
- Leaking cylinder head gasket.
- Worn or incorrect camshaft.
- Loose timing belt.
b. Was a problem found?

[YES] Verify repair.
[NO] Go to Step 13.

13. a. Review all diagnostic procedures within this table.
b. If all procedures have been completed and no malfunctions have been found, review/inspect the following:
- Visual/physical inspection.
- Scan tool data.
- Freeze Frame data/Failure Records buffer.
- All electrical connections within a suspected circuit and/or system.
c. Was a problem found?

[YES] Verify repair.
[NO] Contact Technical Assistance.