I have a 90 accord lx and it shifts harshly and I've read to lubeguard conditioner in the trans fluid and it will help that but how much do I put in? Can this hurt my car?

I also have this big problem that I can't figure out for the life of me...

When it is cold outside and I get in my car drive down the street then go to turn my car off when I put the car in park the red light doesn't light up on the dash and it wont let me take my keys out until that red light is on. So I have to sit there for a few minutes and let my car warm up more and it comes on. If I drive for more than 20 minutes it usually comes on once I put it in park but not always. This is very weird because it only happens when it is cold not in the summer. Does anyone know how I could fix this or what is wrong with it?

Thank you

 

Never heard of Lubeguard, but I have heard of Lucas and Rislone. Not sure if they will help you, but you use half a quart ..... as directed on the bottle. The light sounds like a bad connection, posibly in the switch that tells it that you have the car in park.

 

i have used lube guard and it works really well, it comes in a small bottle, one is recomended but i put in two, will not hurt a thing.
Frank Allen 92 accord