Chrysler Repair: Voyager 2000 missing, 4 digit numbers, grand voyager

Question
We have a Grand Voyager 2000 and recently it has started to stutter. This morning my wife called and said it wouldn't go over 45 mph. Do you have an idea what would cause this?

Answer
Hi Steve,
There is a large number of causes of what is usually called "missing". The best approach is to find out whether the engine controller has noticed any specific problems and stored a fault code in it memory that would give us a clue. Try holding the trip reset button in, the turn the ignition switch to 'run', then release the button. Watch to see if the mileage reading of the odometer window changes to show and 4-digit numbers which would be the fault codes. If that doesn't work then turn the ignition key "on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then similarly watch for fault codes to appear. If that doesn't work then a plug-in code reader will get them. You can get that done for free at an Autozone parts store or for $40 or so at an independent shop. Get the numbers and the meaning of them, then write back and we'll go from there. Tell me which engine you have, please.
Roland