why does my car have to crank several seconds before starting

Have the fuel pressure tested. If the pump or pressure regulator are leaking internally , then it needs to build up pressure each time , before it starts. Make sure the correct specs are used for referrence.DON'T replace parts , without testing/having tested , somewhere with proper equipment.Also have scanned and post code(s). Certain codes may be stored as 'pending' and not turn the 'MIL/check engine light' on depending on the type of fault and/or frequency and duration of it.