Q: Car wont start away I’ve replace starter battery and alternator what else could cause this problem

You will need to be a little more specific on what the problem is you are having? Is the engine turning over at normal speed when turning to start but engine just takes too long before it will start? This may be a fuel pressure issue with fuel pump. If you turn the key but engine turns real slow and not cranking fast enough then this can be bad connections or battery cables and connections are bad. If you can be more specific on the actual issue of what, when and how often it happens, then I can be more specific on possible problems and fixes for you.