I have a Ford tbird 3.8 v6 engine. When I start my car it idle very high around 2k rpm it dies down then returns high. I have to put it in drive when it dies down to avoid it jurking at take off. As I drive it over revs also causing the car to act as if it will not stop. As soon as i release the break it takes off without me even pressing the gas. I was told that it was the idle air control valve. I have replaced this part but still have the same problem. I am on a fixed income right now and not able to seek professional help so taking it to a dealer is not an option. I don't see or hear any air leaks. The accelerator cable and spring seems to be functioning well. I am puzzled at what the problem could be. Also this sort of problem been happening for awhile, it at first only happened while driving and accelerating and would go away if I let off the gas pedal. Now its gone completely haywire.

SOURCE: 2002 Escape

no...the valve can be replaced without any "computer change"...the PCM constantly monitors variations in sensor signal strength and accommodates changes to compensate for this. A new valve will not "un-calibrate" the PCM. The PCM will merely begin a new "data record" for it....with possible slow results at first lasting from as short as one minute to possibly nearly a week of driving.

SOURCE: Slow acceleration from stop and when driving (trying to pass)

I have the same car. So far no problems with the Transmision. I had the Trans oil change out every 60 K Sure sounds like you need to get the Transmision checked. Is the fault light on. I have invested ina fault code reader sure is worth it. 
Good luck.  Vilmos

SOURCE: 1993 (2.0l 4 cyl) Ford Probe Wont Idle when warm.

Josh, Did you output the car's diagnostic codes before you reset the computer?
Just to confirm: your car has the "FS" engine - 1991cc double overhead cams?
built on the Mazda "GE" platform?
does your car have an "engine check light" or "MIL" on the dashboard? if so where and what does it look like and what does do ? ie: comes on when ignition is turned on & goes out after engine starts. or comes & goes out after x seconds. etc etc
are you 5sp manual or auto trans?

does your car have a diagnostic plug with a flip open lid just behind the battery near the front left suspension tower?

SOURCE: POSSIBLE VACUM LEAK I THINK

dave you ran it with a bad 02 sensor so most likely the EGR valve is plugged pull it off and clean it and it should help withte problem.

SOURCE: My 99 ford explorer cuts out and dies when accelerating in drive

You may have dirty or clogged fuel injectors, may also be problems with the ignition system. Might also check the fuel pressure to make sure the fuel pump is working correctly.