Diagnostic Aids
| • | Inspect the flywheel ring gear for damage or unusual wear. |
| • | Shim the starter if applicable. |
| • | In order to add pinion to ring gear clearance a full size shim must be used. Do not shim only 1 starter mounting bolt. There are 3 shims available in different shapes for clearance. All are 1 mm (0.039 in) thick. |
Step | Action | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|
1 | Did you perform the Engine Electrical Diagnostic System Check? | Go to Step 2 | |||||||
2 | Start the engine. Does the starter operate normally? | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 3 | ||||||
3 | Start the engine while listening to the starter motor turn. Is there a loud "whoop", it may sound like a siren if the engine is revved while the starter is engaged after the engine starts, but while the starter is still held in the engaged position? | Go to Step 6 | Go to Step 4 | ||||||
4 | Do you hear a "rumble", a "growl", or, in some cases, a "knock" as the starter is coasting down to a stop after starting the engine? | Go to Step 7 | Go to Step 5 | ||||||
5 | This is often diagnosed as a starter drive gear hang-in or a weak solenoid. When the engine is cranked, do you hear a high-pitched whine after the engine cranks and starts normally? | Go to Step 8 | Go to Step 7 | ||||||
6 | Inspect the flywheel ring gear for the following:
Is the flywheel bent, or does it have damaged teeth? | Go to Step 9 | Go to Step 10 | ||||||
7 |
Does the clutch gear have chipped or milled teeth or worn bushings? | Go to Step 10 | Go to Step 9 | ||||||
8 | Shim the starter motor away from the flywheel by adding shims between the starter motor and the engine block one at a time. Flywheel runout may make this noise appear to be intermittent. Did you complete the repair? | Go to Step 11 | -- | ||||||
9 | Replace the flywheel. Refer to Engine Flywheel Replacement in Engine Mechanical - 4.8L, 5.3L and 6.0L. Did you complete the replacement? | Go to Step 11 | -- | ||||||
10 | Replace the starter motor. Refer to Starter Motor Replacement . Did you complete the replacement? | Go to Step 11 | -- | ||||||
11 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
