99 deville stalling

hi my car is stalling 99 deville the codes are 1554h 1558h 2473h 2471h 1971current I fix the pluges wiers fuel reugler and when it stall for it start i take the black wire off and put it back on and the will start i clean the batt post both black and red but not the wire to the alt i change the throttle senser and i heir a hiss sound by the map /fuel reugler please can some body tell me what is going on:banghead: