I have a 1996 Nissan Altima for the last tow weeks I've been having problems starting the car it would turn over like it needs gas but there's gas in it but won't turn over the first time it did this I waited the next day and it started with no problem drove it for about 5days then it did it again waited a day and it started took it to a repair shop told them to give me tune up they didn't do it oh and the Check Engine light been on for about 2months so they did diagnsos results are P0325 Knock Sensor P0300 Misfire P0171 Bank Lean OK the mechanic told me this had nothing to do with the car not starting so after I left car with him it start for him so he said the only way he got the car to start was when he turned the key real hard forward so he say it was a bad ignition switch he removed and replaced it oh and I'm a single lady so I don't know anything trying to learn so got the car back turned it on with no problems Monday drove home and everything he charged me over 300.00 dollars for oil change ingnition swith and diagnosis Tuesday check engine light back on and car won't start same problems car will turn over but won't crank over battery good tried to get jump nothing so does anyone have any suggestions went to autozone and asked about codes and knock snesor does this knocke senscor have anything to do with the car not turning over