alero problem
 

OK, I had posted before about car starter not working, replaced starter ran fine, drove to work and turned off car would not start, cranks spits sputters backfires. Replaced ignition switch, put in new plugs did diagnotisic said all ok, now starts runs 15 sec shuts off. Start back up runs spits sputters backfires had code of 0440 which could be from too much gas. replaced fuel filter, still same I am trying to fix so I can get rid of this thing any more ideas, will idle but if you give it gas engine seems to sputter, rpms go up then dies backfires when you try to start it back up next is fuel pump? or is it electrical? Thanks

in addition
 

When I had garage replace the ignition they said the plugs were gas fouled and replaced them, after I picked up car did same thing they looked at it again said fuel ingectors were "wide open" and plugs were soaked but car started up, they had it for two more days said I might have to take to dealer to have BCM interfaced with new ignition. The backfire might be from all that fuel thats in there?

If the injectors were staying open too long or stuck open you would get a code for that. It sounds like you have a valve stuck open.