While I'm driving my Grand Am GTSE,if i hit a bump in the car turns off,I

I agree with answer from Greg's Auto Orange as I too had this problem...turns out that among the multitude of problems with Pontiac Grand Am's made between 1999-2005, one of them is corrosion of the connectors for the power cables at the battery. Particularly the positive cable connector, this makes for a poor connection and makes the connectors giggle loose. Hence why it would happen intermittently or when, as you stated, hit a bump. A more serious problem wouldn't be so easily remedied! When it happened to me I was wracking my brain when it wasn't caused by the usual problems that plague this car i.e. Passlock Sensor issue that causes the Security light in dash to come on blinking...man do I loathe seeing that start blinking...turning your key to the On position and sitting there for 20 minutes isn't quite ideal...anyhow a simple tightening or if real corroded a cable swap out should fix this problem easy. Did for me and hasn't happened since. Oh by the way the connector on this car is a post and once it comes loose you'll need a 5/16ths ratchet not very easy to handle with the awful side posts we're stuck with...I invested in a special battery ratchet...works like a charm...good luck!