I have a z06 with a rpm lvl 6 4l60e, it wont pull down into 1st gear, when in over drive it starts out in 3rd but you can pull it into 2nd fine. it has a PCS trans controller, I talked to a guy at PCS he said if the controller wasn't working it would only have reverse and 2nd, so it is working I guess? so I have 2 main issues, why is it starting in 3rd and don't have a overdrive and why wont it pull into 1st? shifter pops back out. I adjusted the linkage below and when pulling into 1st its like it gets stuck between gears and the red mark is off on the shifter? any common issues?

 

Check shifter adjustment. If that checks out, Unhook the shifter cable & manually check/count all the detents (PRN4321)

4L60E's will default to 3rd gear with both shift solenoids OFF, 4L80E'a default to 2nd. Call PCS back & talk to someone who knows what the hell their talking about.

 

Righto.
If the controller isn't working, or even hooked up, you would only have 3rd and Reverse.
If it pops out of D1, you have a shifter adjustment problem.
What plate is bolted to the shift shaft on the trans?
If the B&M with multiple holes, you may need to try a different hole.