I have a 2002 Dodge Dakota 3.9 4x4, and have had this problem for the last 3 years and 35 thousand miles. When it first starts it runs rough, not smooth at all. Then as you drive it coughs and pops (sounds like someone with a baseball hat under the hood). It will accelerate a little, how much depends on the day but usually around 25-40, while kicking and coughing. When it does this it will hit a point where it has very little power, feels like your pulling 20,000 lbs. If you keep your throttle steady, you wont accelerate anymore, floor it and in within 5 seconds, it gets full power back and kicks in strong. Like someone hit a NOS button. Sometimes it will come back sometimes its gone. The problem comes and goes randomly, its only a problem for the first 5 minutes after it starts then drives fine. I have had engine code 0300,0301,0303, Multiple cylinder misfire, cylinder 1, cylinder 3. P0351 Ignition Control. 0420, I replace driver side catalytic Converter and rear O2 sensor, and now have 0172. I also have replaced plugs, plug wires, and MAP sensor. I look on a scanner, even when I floor it the Throttle position reads 67% is that normal? The MAP reads close to 100 kPa. As for the engine codes I usually clear the code and it will go away, this hasnt been a consistent problem. Usually will last for a week or two, I put in a bottle lucas fuel injector cleaner and it goes away for a month or too. I cut back my driving by about 150 miles a week for a year and during that entire time I never had this problem. It seems to be more frequent when the weather is colder. Im not sure to what degree the timing should be advancing but im thinking I either have a crank position sensor, cam sensor, TPS, ignition coil or maybe a bad ecu? If anyone has any idea or suggestions please let me know. Thanks for the help.