My 1999 saturn sl2 car starts every time. But when under a load its chuggs and sputters. Also chuggs every time you shift. The car is a 5speed. Egr has been replaced. And its throwing code over and over. It also the code p1635, po171, p0410, p0341. Im starting to think its a ecm problem. The motor was rebuilt my a shop in town 20000miles ago FYI.