66plyValiant,
I have a nos mopar tbi, it uses a motor and cheap gears to drive throttle. I think it would suck on a good day. The GM likely uses a stepper motor for orfice flow control, they require much baggage to drive. My simple and reliable solution is a neon idle control air bypass solenoid. I have the driver built into my ECU, it uses PWM and a PID control strategy. It has worked very well on the numerous cars I have injected. I developed the system to replace the unstable idle control on my old BMW 528e. It worked well, so I built the feature into my ECU. Bosch had a similar system on VW, Volvos, and Porsches, while they have a bypass air, the solenoid operated a shutter that would gum up. The Neon valve is self cleaning and reliable. I just fabricate a manifold for hoses, on the 2.2L Mopar turbo, parts to replace the sick motor/shutter assembly.
Del,
I find I forget that working on cars requires R&R. I get out couple times a day to do my animal chores. They are always there to meet me. I wish we were closer, I would share my EMS. The hardware is inexpensive, less than any other solution including MS. I would trade it for goulash.