Symptom guide
Car Cranks But Won't Start
How to narrow down a normal-cranking no-start into fuel, spark, air, compression, or sensor problems.
Quick answer
If the engine spins normally but never catches, the battery and starter are probably working. Focus on fuel delivery, ignition spark, crank sensor input, or engine timing.
Most likely causes
- Fuel pump failure
- No spark from ignition coils
- Crankshaft position sensor failure
- Flooded engine
- Timing belt or chain problem
Basic driver checks
- Listen for the fuel pump prime for a few seconds when the key is switched on.
- Check whether the tachometer moves slightly while cranking.
- Scan for stored or pending OBD-II codes.
- Note whether the engine smells strongly of fuel.
DIY diagnostic path
- Use an OBD-II scanner before disconnecting the battery.
- Check fuel pump fuse and relay locations in the owner's manual.
- Inspect ignition coil connectors for loose plugs.
- Do not spray starting fluid unless you understand the intake and fire risks.
Common mistakes
- Calling it a starter problem when the engine already cranks
- Clearing codes before writing them down
- Assuming fuel pump failure without checking fuse, relay, and power
What to tell the mechanic
Say that the engine cranks at normal speed but does not fire. Share any codes and whether the fuel pump can be heard.