I have a 1996 3.8L convertible with a 4spd auto. Whenever I get in the car, it likes to do this thing where it rolls like it’s in neutral when i press the gas in drive, then throws itself forward and starts to drive. Then while i’m driving, i will be going around 50mph, and it will continuously shift from 2nd gear at high rpm’s to 3rd gear at low rpm’s, if i press the gas at all while it does this, all i get is a loud rev from the top of 2nd gear. I’ve done everything to try and make myself think it’s not a transmission issue like change the oil, change the rear differential fluid, change the purge valve canister, maf sensor, o2 sensors, and air filter. This is my last resort for help. If there is anything anyone can suggest to help i would be so grateful.