Car cranks but won't start
The buyer question: "car cranks but won't start"
Avoid repeated long cranking. Stop if you smell fuel, see smoke, the battery gets weak, or the engine sounds abnormal, then arrange a proper diagnosis.
What could cause it
More than one problem can cause the same symptom. These are places to inspect, not a diagnosis.
- Fuel delivery or fuel-quality problems
- Ignition or engine-speed sensor faults
- Air, throttle, or control-system issues
- Timing, compression, wiring, or immobilizer problems
Safe things to check
Keep clear of moving parts, hot components, and traffic. Use the owner's manual for vehicle-specific instructions.
- Note whether the engine cranks at a normal speed and whether any warning light or security message appears
- Check the owner's manual for the correct key and fuel-system procedure
- Do not spray unknown fluids into the intake or keep cranking with a strong fuel smell
Do not keep cranking a car that will not start in a confined space or near a fuel leak. Stop and get professional help if fuel odor, smoke, or unusual mechanical noise appears.
What a mechanic may check
A technician may verify the battery and cranking speed, scan codes, check fuel pressure, spark, engine-speed signals, compression, timing, and security-system status.
If you are considering this car
A seller who says the car only needs a sensor still needs to show a diagnosis. A no-start car needs an independent inspection and repair proof before you treat it as a normal candidate.
Questions for the seller
- Does it crank at normal speed, and is the problem cold, hot, or constant?
- What codes or tests identified the suspected cause?
- Will the car start repeatedly for an independent inspection?