I have a 2002 pontiac gran prix gtp supercharged an have had high idol an car would shut off when slowin down.i have replaced idol control sensor,mass air flow,coolent sensor an now have sputter badly

I have found no vacuum leaks an its fuel injected so no throttle body.ive been all threw all an cant seem to find the problem..need help....

No vacuum leaks its been checked an no milky goop on the oil stick.i was told maybe it is the egr valve? But i took the egr off an cleaned it like i was told but it didnt help any.

My light is unhooked or something it has never came on at all an i took it to advance auto an they scanned it an its showing now the problem is the fuel injector 3 bad an is still showing all the new sensors i put on the car are bad..i just dont understand..sorry im a woman an tryin to do this alone an im not mechanically inclined..thank you for helping me

I would have said injectors... Sounds like it needs some serious TLC... How long have you owned the car? Are you looking to keep it?

check the fuel pressure regulator. That is exactly what mine did. look for raw fuel sucking into the throttle body through the vacuum line coming from it.