Actually, if you are not getting codes, make sure the wiring harness to the PCM is tight and clean. Also, check the power distribution box / relay box under the hood for fuse problems.
As far as the 1 - 2 shift, chances are the shift solenoid is bad. There are two of them. One is for the 1-2 shift and the other for 3-4.
Let me know if you have other questions.
Saturday, January 2nd, 2010 AT 1:45 AM