problem only happens when trans is in 1-2. other than that it shifts fine. any thoughts?

???

Mine too.I suggest you leave it in "D".

If you're talking about putting the shifter in the "1-2" gear... You have to rev it really high to get it out of 1st. Instead, just put it in drive, let the tranny shift to 2nd then put the lever in "1-2". Otherwise it's hard to get it to shift out of 1st since it's a super low gear.

The tranny will stay in 1st gear until it hits the rev limiter basically. That drive option is there for towing or if you need to stay in 1st gear in mud or snow. If you want to switch it to 2nd, there are ways to wire up the shift soleniods to do so. It's perfectly normal for it to seem like it won't shift into 2nd when in that option. Don't worry about it. Just drive with it in D. If you go from D to 1-2 while moving, the tranny will act as a manual and downshift to 1st fairly quickly. I don't recommend doing that. Only shift into the 1-2 position if you are going like 25mph and under. Also, it will jerk pretty good if you do that.

my 89 jeep will shift into 2nd when in 1-2 at about 4500 rpms, same as if you get on it in comfort mode.

Do you keep it in comfort? Keep the switch on power, it runs better that way. Not a very big difference in mpg either. I honestly think I got better mpg in power because it shifts better and doesn't bog down on hills when it tries to save gas. I never rev mine more than about 4000rpm, since I have 235k and the good ol' renix has no rev limiter. I gotta watch when it gets a little slick out in the rain. Sometimes I slip pretty good starting off from a stop sign.

I usually leave it in power cause it shifts better, feels like it slips going into 4th in comfort and my exhaust just sounds better in power mode, Straight piped out the side after the cat, my muffler just fell off one day.

Haha, nice job on the exhaust. I have a side exit after a Cherry Bomb Extreme muffler. I gotta get a custom 2.5 inch tailpipe bent before inspection time comes around. I do like the way mine sounds though I definitely feel it shifts better in power mode. It lets the engine perform to it's full potential.