- Worn Starter Drive Gear: If the starter's drive gear that engages the flywheel is worn, it can cause a screeching noise. This gear's teeth might be chewed or damaged, resulting in a grinding noise upon engagement.
- Misaligned Starter: Improperly aligned starter position or improper installation of the starter motor after servicing can cause the starter to engage the flywheel incorrectly, leading to a screeching sound.
2. Flywheel Tooth Damage:
- Damaged Flywheel Teeth: If the teeth on the engine's flywheel are damaged or worn, it can create a screeching noise when the starter drive gear engages with them. This damage can be caused by excessive wear or mishandling during engine service.
3. Engine Harmonic Balancer Damage:
- Cracked Harmonic Balancer: The engine's harmonic balancer is designed to absorb vibrations. A cracked or damaged harmonic balancer can cause the starter to make a screeching noise when engaging.
4. Worn Flex Plate (Automatic Transmissions):
- Automatic Transmissions: If the vehicle has an automatic transmission, the flex plate on the torque converter can sometimes develop cracks. This can result in a screeching sound when the starter motor engages the flex plate.
5. Engine Problems:
- Lack of Oil: Insufficient engine oil can lead to metal-to-metal contact between the starter drive gear and the flywheel, resulting in a screeching noise.
Addressing this issue should be prioritized because a screeching noise when starting the engine indicates potential problems that could escalate and cause more severe engine issues. A professional mechanic should diagnose the exact source of the noise to determine the appropriate solution.
