just put a transmission in my 96 cherokee 5.2lte v8. for some reason it will not start in park so i have to put it in netural and it starts just fine and when i put it into park it instantly dies, it will go into drive and reverse but it kinda lunges and like if i let off the brake it takes off so i have to hold the brake so it dont move. maybe i did something wrong? ive never seen anything like this and it is irritateing the piss out of me because i cant figure it out. any ideas?