Out of ideas. Please help!

I bought a 93 mgm about a month ago just to drive back and forth to work. When I start it up for the first time of the day it idles sparstically, high rpms the low, over and over untill I put it in gear. When I drive down the expressway it does fine untill I get on the exit ramp. When I let off the gas pedal the engine is still getting gas but the pedal comes all the way back out. At that time the check engine light comes on. If I just tap on the pedal it will idle back down. I put the car on a diagnostics test and it said "low voltage signal form the tps". I put a new one in and still had the same problem. My buddy said he had that same problem and it was the fuel pressure regulator. Then I did a fuel pressure test and it was bad sure enough. I changed it out but I still have the same problem. Any help or ideas would be great!

What were the fuel pressure readings you got? Usually a pressure regulator will not cause a loping idle. You may need to sheck the idle speed control motor. Also they were bad about carbon dlogging the intake passages under the throttle body. If you have it scanned again, please post the exact code numbers. Not the description. Thanks.

The fuel pressure regulator was bad because it wouldnt hold presssure. Engine not running it fell below 30 psi. within 5 minutes, about 3 minutes to be exact. The Haynes manual says its bleeding off too fast. With the new one its holding pressure. When I bought the car the codes were 125,135,132 and 122. After I put the new tps on, its reading 125. That is the only code it is reading now. A man at Autozone said that the idle air intake valve probably had carbon build up and he showed me what a new one looked like but I dont see anything that looks even close to the part he showed me. Thanks for your input.

The Idle speed control motor is located down behind the motor to the drivers side of center. It is hidden and hard to get to. Here is a picture of a similar part.

http://usera.imagecave.com/way2old/iac.jpg

Silly question, is the idle speed control motor and idle air intake valve the same part? If it is then that is why I couldnt find it lol. Thank you so much for all your help. I work 7 days a week so I hope to check this out soon and Ill let you know if that was the problem.