I have a 2004 town and country AWD. it acts like its in limp mode. cannot get it out. tryed several different methods still no joy. so beteween me and the guy who i got it from its got new valve body in the tranny, new input and output speed sensors and new shift solenoid pack, new TPS, fluid and filter. keeps throwing code of third gear ratio incorrect. also swapped out the ECM and immobilizer for a different one [ not new just different ] but put the original back. is there a common cause for this on these minivans or is it a hit n miss fix?