Pontiac Repair: Car is not running properly, throttle position sensor, pontiac firebird

Question
Hi,
I have a '91 Pontiac Firebird 3.1 engine.
I have have had trouble with the car for serveral years and have replaced most everything I can think of. Some several times.
When I start the car and it is ideling and step on the gas, it sounds like it is getting too much gas. After I step it down it will come out of it. But each time I re-start it it will do the same thing. This has been on going for several years. Fuel pump has been replaced and the oxygen sensor has just been replaced for the 4th time. The injectors have been replaced and checked a couple times,thinking that was the problem.
Also the car acts like it wants to die when I slow down and coming to stop. It gets like a second wind and will come out of it. However,not always. It has literlly died on me if I'm driving in a cruse type idle position going down the street. At which time I have to bring it to a complete stop and restart it. It starts again with no problem at this point. I have suggested the idle sensor be checked? ? (But I have no idea)
The check engine lite was coming on and he replaced the oxygen sensor.That is not coming on for right now. But I hate to say anything too soon. So much has been replaced it's hard to say what hasn't been. Including the main computer.
I surely am not a machanic, but to me it's like some kind of sensor that is not working right for the amount of gas it is getting or not getting.
I have all the records, so everything can be checked back on.
Can you help me? Any ideas?
You can post this on your site for information for anyone this might help.  

Answer
Sounds like it running to rich. Could be a coolant temp sensor reading to low. Could be a throttle position sensor(TPS) out of adjustment. There are a lot of things that it could be. Your best bet would be to take it to your local Pontiac dealer and have it properly diagnosed. It will cost you less to have it diagnosed than to keep throwing parts at it.