Will a bad or stuck EGR valve cause engine problems even while in open loop mode?

I have a 91' T/A GTA w/LB9 and a 700r4. Its idleing very rough to the point it wants to die. Above 2800rpm or so it gets it power back. While it is running it has a VERY rich smell and wants to smoke black smoke. I used a code key and couldnt get any codes so a friend brought a scanner over and it sayed it wasnt connected. I checked 3 grounds under the hood and adjusted them for a good connection and that didnt work. The grounds were 1) Firewall to Right head 2)black wire grounded to front right fender 3)black wire grounded to front left fender. I also checked the voltage on my TPS-MAPS-new O2s-IAC-etc. They all read fine. BUT....my cars been down for about 2 weeks. A week ago i pulled 2 vaccum lines off the the EGR solenoid and put them back on and it ran fine for about 2 days. Now its doing the same thing again. Hence though when i pull the vaccum line off the brake booster i get a regular idle but if i hit the gas it hessitates and "backfires" through the intake. What could this be and why isnt my ALDL working? Please help

 

i got the same trouble with mine -I'm guessing somethign to do with either the EECS cylinder (if there's a lingering fuel smell) or the EGR valve ... did you cure your problem ?

 

I get an intermittent problem similar to that, but mine is a problem with the TPS voltage. If it senses it needs more gas low, then it gets it, right? I can't see why the EGR valve would affect that. Just a thought.

 

thanks for the info but i fixed it now. It was the ECM.