Transmission kickdown cable adjustment 4.3.1st gear winds out too high,seems to skip 2nd goes to third doesn't seem to go in O.D.service engine lite is on.used a sensor tester and diagnosed bank 1 was bad.replaced sensor driver side after exhaust manifold.still on still won't shift proper.catalitic conv. rattles.plugged?

Don't really know for a fact it's your problem friend, but to adjust the cable, which controls shift on this style trans, leave engine off, raise hood, open throttle completely by hand, stick your finger, or something of the sort, into the opening on top of the plastic cable connector and depress the button on top over top of the cable. This is a ratchet action cable adjustment, when depressed the cable will fly back into the housing. Then the cable is adjusted automatically by the transmission itself and you need do nothing more. It's just GMs way of getting something serviced so it doesn't get screwed up by the owner or shade tree mechanic. See if it shifts properly now. If not yet, drive it a bit and give it time to adjust to its new setting. With the 700R4 and 4R200, could be either in your vehicle, has a lower first gear and normally will shift right away into 2nd gear after moving a few feet. So it should go to 2nd gear without much time involved. You can't hold these tranny's in low either. They will still go into second while holding the shifter down in first. Just the nature of the beast. I thought it best you know these things. Now, this one thing may not ever happen, but IF ever it will not go into overdrive and will stay in 3rd gear no matter what you do, it means the trans must be rebuilt because the OD is shot. Possibly the drum scarred and burnt up inside on OD.