i have a 1986 lx5.0 auto mustang it has over 110,000 miles when i start my car up and put it in drive it feels like it is in neutral and then i rev it up to about 1500 rpm then it catches it does it everytime i start it up. but once i get going down the road it is fine. it has also done it in reverse the rpms get really low and the engine shuts off. also i have gone through 2 starters and the last one i had pink grease inside of it

 

check the fluid level!!while car is running