Drive 2007 grand prix. wont even turn over or click.lottsa batery. Everything works. Just wont start or turn over. When starts and I drive it, then stop and turn off,sometimes wont start. Half to sit a few min. then will start. sometimes. May not start till next day. Can stop for gas then try to start and wont. half to play with keys to get to start.

SOUND LIKE ALTERNATOR NOT CHARGING BATTERY.CHECK BATTERY VOLTAGE SHOULD BE 12.6 VOLTS.MAY SURE BATTERY CABLES CLEAN AND TIGHT.WITH ENGINE RUNNING CHECK ALTERNATOR OUT PUT AT BATTERY.SHOULD BE 13.5 - 14.5 VOLTS WITH ENGINE RUNNING.IF ALTERNATOR FUSE GOOD AND ALTERNATOR BATTERY FEED WIRE AND VOLTAGE REGULATOR WIRES OKAY NOT DAMAGED.DRIVE BELT NOT SLIPPING OR BELT TENSIONER NOT DAMAGED.ALTERNATOR MORE LIKELY FAULTY.TURN OFF RADIO FIRST.BEFORE REMOVING NEGATIVE BATTERY CABLE TO KEEP FROM LOSING RADIO CODE.