Yeah, you may be right on your car not having an EGR valve.

Today, I finally had a chance to do like everyone said and check the vacuum lines under the hood. I changed out the check valve at the vacuum resevoir, replumbed the vacuum lines at all locations. Interestingly enough, since a modulator valve was only $12 at Autozone, I picked one up and low and behold, when I took it out, it was trashed! New one installed with proper new vacuum hose eliminated the parking situation whereas I couldn't shift the car out of park. I'm happy about that. So, I still have no vents on dash though and it is stuck in defrost mode. I plugged the cruise module, put the HVAC on A/C "MAX" and from outside the car held my hand over the vent and nothing happened when I physically plugged the vacuum line going to the cruise module. I then proceeded to unplug the hose going to the check valve at the brake booster. The car immediately started idling rough, like I suspect you all referred to in earlier posts. Physically plugging that hose with my thumb made no change in vent either. I am leaning towards a faulty upper or lower actuator on the car. The electronic blend door actuator works fine when switching from hot to cold. (I can see it moving since I have the glove box tray out.

Has anyone ever run into this before? Keep in mind, I already changed the vacuum control head and the switch on the HVAC control on the dash....

The only other vacuum I didn't check was the vapor line switch//////?????

You said you ordered a new HVAC control unit. Did you receive and install it yet?

yes....I'm looking at another posting here under Buicks and they say to check the violet line coming in for vacuum? I'm going to go check that quick as maybe the resevoir is bad? I'm stumped!

SOLUTION FOUND!!!!!!
Upon inspecting the black vacuum line on the psgr side (under the glove box) I realized there was no vacuum. Knowing that I had vacuum before the resevoir on the firewall, I therefore took the resevoir off and found the problem. The resevoir had split at the seam along the top of the cannister. This is almost impossible to find as it is located under the weatherstip seal for the hood. I used a blue pasty type RV silicone gasket maker around the entire vacuum resevoir to ensure that the seal was good and replaced afterward. Started engine and whala! Eureka! By George we got it!
Thanks to all me friends here on GMForum for helping me to diagnos and repair this.
And remember, if you have no air at the vents, first inspect your vacuum line between TBI and firewall mounted vacuum tank. If you still have no air at vents, check the black vacuum line under the glove box that mates with the violet colered vacuum line running to control head. If you have no vacuum at the black vacuum line inside> check your vacuum cannister reserve tank for leaks! I hope this saves someone a lot of time and frustration!
Blessings!
Rev. Randy

solution found at end of thread!

Good find. Justin had you on the right track.