Starting problems

Grinding noise from the starter when starting the car

A harsh grinding sound when you turn the key usually means the starter's small gear isn't meshing properly with the engine's flywheel, which can wear both parts if ignored.

Difficulty
Moderate
Time
30–90 minutes (diagnosis)
DIY cost
$100–$300
Pro cost
$250–$700

Symptoms

  • Grinding or growling sound briefly when starting
  • Engine may still start despite the noise
  • Noise may get worse over time or happen only sometimes
  • Can sound like metal scraping metal

Likely causes

  • CommonWorn starter drive gear (bendix)This small gear engages the flywheel and wears out from repeated engagement over time.
  • PossibleWorn flywheel/flexplate teethIf the teeth the starter gear meshes with are worn, grinding results even with a good starter.
  • PossibleStarter mounted loosely or misalignedLoose mounting bolts can prevent proper gear engagement.
  • PossibleWeak battery causing slow, incomplete engagementSlow cranking speed can cause the gear to grind instead of engaging cleanly.
  • Less commonWorn starter solenoid componentsInternal wear can cause mistimed engagement of the drive gear.

What to do

  1. Note whether the grinding happens every time or only occasionally, since occasional grinding often means one worn tooth on the flywheel.
  2. Stop turning the key immediately if you hear grinding, rather than holding it, to limit wear.
  3. Check that the battery is in good condition, since a weak battery can contribute to poor gear engagement.
  4. Inspect (or have a mechanic inspect) the starter mounting bolts for looseness.
  5. If the noise is new and infrequent, have the starter and flywheel/flexplate inspected before it worsens.
  6. Avoid repeatedly cranking through the grinding, which accelerates damage to both the starter and flywheel.
  7. Have a mechanic check starter engagement and flywheel tooth condition, since replacing just the starter won't fix worn flywheel teeth.
  8. Budget for possible starter and, less commonly, flywheel/flexplate replacement if grinding is consistent.

Tools and parts

  • None for diagnosis; a jack and stands for inspection
Starter motorSearch: “starter motor for [year make model]”
Flexplate or flywheel (if worn)Search: “flywheel or flexplate for [year make model]”

When to call a pro

Grinding that continues or worsens should be inspected by a mechanic soon, since it can eventually leave you stranded or damage the flywheel further.

Safety

Use caution

Working under a vehicle to inspect the starter requires proper jack stands, never just a jack, to prevent the car from falling.

Related guides

Operator provides AI-generated troubleshooting information. It can be wrong. For safety-critical, electrical, gas, structural, medical, automotive safety, or other high-risk problems, consult a qualified professional.