If the engine turns over normally but will not start, see the fuel, ignition, sensor and immobiliser clues that help narrow the fault.
If the starter turns the engine at a normal speed, the basic cranking circuit is doing its job. The next question is why the engine is not producing combustion.
A lack of fuel pressure, injector control, ignition spark or correct mixture can stop an engine firing. Petrol and diesel engines use different systems, so the vehicle and symptoms matter.
Crankshaft or camshaft sensor faults can prevent the engine control unit from knowing when to inject fuel or trigger ignition. Timing faults can also create a crank-no-start condition.
OBD-II codes can narrow the system involved, but a code naming a sensor circuit does not automatically mean that sensor itself has failed.
Describe exactly what is happening and AutoAid can use the details, saved vehicle and any OBD-II code to narrow the likely causes.
Start a diagnosisSee all symptom guides →Symptom pages are a starting point, not a confirmed diagnosis. If the vehicle has a safety-critical problem, stop somewhere safe and arrange professional inspection.