1999 Pontiac Grand Am running rough

Engine Performance problem
1999 Pontiac Grand Am 4 cyl Front Wheel Drive Automatic 125k miles

hi
im having problems with my 99 grand am when you start it up and switch it to drive it has a really rough idle, and smeels like alot of fumes- and it gets worse as it heats up by the time it reaches normal operating temp. Its vibrating alot but its not as bad in park or neutral, were its only a slight rough idle then- nor is it bad anywhere else but idle the car has tons of power you can do 70mph on the highway barely tapping the gas and have tons of power on hand. At idle you switch it to drive its really bad in fact every time I stop the car I have to switch it to neutral, I can tell it runs really rich I am dumping fuel right now and I smell fumes and its also idling at about 525rpm maybe 550 rpm. And when I turn the ac on and engage power steering its dosent move at all and it does not move when switched from neutral to drive either it still idles at 550, which is why I just ordered an IAC to see if this will help my problem. Sometimes it struggles to start a little bit not much maybe an extra second or two though. I work on this car myself and have done alot of work recently such as water pump, timing chain, guides and tensioner, exhaust manifold gasket, intake manifold gasket, egr clean screen gasket, cleaned the iac and port and the throttle body when they were off, o2 sensor, ect sensor, iat sensor, thermostat, s-belt, battery, coolant flush, transmission service, air filter, fuel filter(115k), heater hoses and rad. Hoses, pads and rotors, and I did all this myself I take good care of the car I even change the oil every 3k-3500. Maybe you can help me figure this out also I used a bosch 02 sensor and I am about to get rid of it and go back to the ac-delco it came with as I am hoping that might help with the gas mileage. I checked for vacuum leaks and did the manifold gasket as I mentioned I also sucked on the fuel pressure regulator line to see if it was dumping fuel into the intake but I got nothing, my brakes have been harder to press even after I did them so I sucked on the brake booster vac. Line and got nothing as well: on my list right now is the iac and the oem oxygen sensor, after that I was thinking maybe the FPR I would change anyway, if you have any ideas to help me they would be really appreciated as I am almost out of things to check and I am heading towards spending money on potentially not needed parts, most of the work I did already was just things that needed to be done anyway not really trying to fix the idle problem. Please help thanks alot--JON