1999 trans problem

ok here we go i have a 1999 Monte Carlo 3.1.
alittle back round on the problem, we went off with the car and everything was great and on the way home it was working great till we pulled away from a stop sign and the car wouldnt shift out of first un less i let off the gas and then it would but when i stepped on it to go again it would shift out of second back in to first at least two times untill it would stay in second and it goes through all the other gears just fine. we stoped driveing it cause we thought well the tranny is going out. it didnt through any codes at all for the tranny. first i drained the fluid and changed the filter and they both were clean like they were just changed before that. then i added some transtune thinking i might have a sticky valve in it and it would clean it up. the car still does it. tonight i fired it up after sitting about 4 months and took it for a drive and it did it again and my check engine light came on. i hooked my scanner up to it and it finally through code " P0753 Shift Sol A CKT Electrical "
what does that mean and how big of a job is it to change???

Side cover must come off to access the solenoid pak, that requires removing the axle and at times the trans and subframe dropped down for the side cover to clear the side rail.

ok thank you, now when i get in there it will there be more that the one solenoid there or is there just one?? if there is more than one how do u go about figureing out which one it is

Check this link. http://www.automotiveforums.com/vbulletin/showthread.php?t=685922