4l60e? Limp mode
 

My new tranny has worked find for the first month of the install. Now I'm having 1-2 issues and it only goes into o/d after 90. I'm at 3000rpm and believe that to be correct with 3:23 for o/d. I'm pulling a 1-2 solenoid code but before I change it I want to make sure I don't need to check or replace anything and waste $40 on fluids and another gasket. The tps is .5 volts and smooth throughout the range ending in the high 4's 4.8 I believe. This tranny wasn't rebuilt, everything in it was upgraded and a 3000 stahl revmax converter installed. I'm wondering if a ground? Wiring issue? Vss sensor, or computer problem could cause this. The computer hasn't been tuned yet because I was waiting for the rest of the exhaust install. Also the battery needs to be replaced. Car will always start but if key left on for ten minutes battery is dead. I've spent so much on this 97 z28 I just haven't picked up a new battery yet