Hello i recently bought a pontiac grand am gt with a 3400 v6 and have had some troubles finding a solution to my problems with the vehicle, when i come to a complete stop (periodically, it doesnt happen all the time) it will idle for a minute but when i let off the brakes to hit the gas everything will shut off and it will take a couple tries to restart, but when i go to start it from just sitting before i go somewhere it will start up just fine, ive replaced the catalytic converter because the old one was clogged. One of the throttle body bolts was loose, the main vacuum hose had a huge leak because it was barely on the fitting so we pushed that back on, replaced another vacuum hose, the weirdest thing is that its not throwing any codes and i was told it could be a sticky injector or a fuel pump about to go out but i was hoping i could get some advice from some people who might know more about the problems these vehicles might have

 

There is a small u shaped hose in the evap purge system near the egr valve. It becomes rotten and collapses. Replace it.