Couple weeks ago had to have my fuel pump replaced. When I got her back she was idling kinda low then normally. Mentioned it to the mechanic and he told me to drive it give time for the computer to adjust. Ok fine did that truck started running fine. Last week while waiting for my wife the Rpms dropped then she shut off. Turned the key and started right up. Then later on that day same thing Rpms dropped then shut off this time it took a couple of cranks to start. Went to home cleaned the maf and throttle body. She ran fine for a couple days then shut off again. This time didn't want to start. Kept cranking but nothing drained the batt. Called my brother in law. Gave me a jump and she started right up. Changed my battery thinking it was old already and wasn't holding charge. Again ran fine then in the Sears parking lot she wouldn't start. Kept cranking and nothing. For some reason I disconnected the battery for a few minutes hooked it back up and she started right up. This has me scratching my head and I really don't want to take her to the mechanic ive given him way too much of my money this year. Any help or opinions would be appreciated!