Chrysler Repair: sporadic miss/limp-in mode, 4 digit numbers, spark plug wire

Question
between 45 and 50 mph you feel a miss sometimes regular miss    sometimes and irregular miss seems to be cylinder 1    not noticeable accelerating or above 55 mph.1999 ram 1500  318

second question- 2002 2.7 intrepid ------ when slowing down at 19 mph sometimes he transmission will down shift and not resume shifting unless you turn the ign. key on and off then it will go to regular functions. this has been going on for 15000 miles

Answer
Hi Mike,
A single cylinder miss, because you have localized, is likely due to a spark plug wire whose insulating properties are compromised, a worn/mis-gapped spark plug, a faulty injector or its wires to the pcm/asd. I don't have manuals for that engine so can't give specifics on checking the wires. But take a look at night, in a dark location/high humidity situation to look for arcing along the spark wire. Then take a look at the plug, finally consider changing the injector or cleaning it.
On the failure to up-shift, that is likely a default to 'limp-in mode' where-in the trans refuses to shift out of 2nd. It is a fall-back position designed to minimize potential damage when the controller has logged a trans fault. The best approach would be to do a readout of the comtroller via the ignitiion key:"on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the odometer window to see mileage change to instead show 4-digit numbers preceded by a P which are the codes. Let me know what you find and we'll go from there.
Roland