My car cranks but won't turn over is it because my oxygen sensor need to be replaced
My car has a manual transmission.
You could completely remove the oxygen sensor(s) from the vehicle and that would not prevent the engine from starting. However, if you have a bad coolant temperature sensor which prevents the ECM/PCM from adjusting the air fuel ratio at start-up, that is an example of a component that could prevent the car from starting. Prior to performing diagnostics be sure you have a fully charged battery that passes a load test. Then, confirm that the engine immobilizer system (security system) is not activated thus preventing the car from starting. Basically, if a fully charged battery is powering a starter motor that is turning the engine over rapidly, at sufficient RPM, but the engine does not catch and run, that means that there is an ignition, fuel, air induction, or mechanical fault in the engine that will have to be repaired. Be sure there is adequate fuel in the fuel tank and that the fuel is not old. Check for adequate fuel pressure...does the in tank fuel pump "whir" momentarily at the instant you turn the key to the "on" position?; if not, you have a dead fuel pump. Check injector operation and for a spark at the spark plugs. In your circumstance, is the vehicle’s Check Engine Light illuminated? If so, there will be diagnostic codes that might get you in the general area of the problem. If the simple checks I outlined above do not result in the car starting your best option is to request a no start diagnostic. During such a diagnostic, a certified mechanic from YourMechanic would use a code scanner to retrieve any available diagnostic trouble code(s) from your car’s ECM/PCM that will identify the "system" or area of the fault. If there are no codes to read, the checks above (fuel, air, ignition) would be performed to pinpoint the problem. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.