What could lead to 1AZ-FSE engine cannot start it cranks and fuel is coming out but only spark is coming out?

If the 1AZ-FSE engine cranks and fuel is flowing but fails to start, the issue may lie in the ignition system, specifically a faulty ignition coil or spark plug. Additionally, problems with the timing, such as a misaligned timing belt or camshaft, could prevent proper combustion. Electrical issues, such as a weak battery or poor connections, can also lead to insufficient spark strength. Lastly, ensure that there are no issues with the engine's air intake, as inadequate air can also prevent starting despite fuel being present.