1990 Legend LS, Auto
180k miles

My transmission seems to slipping. When it is cold, it is providing very little torque and consequently moves very slow from a stop. once i gain some speed and it shifts into high gear it seems ok. The sluggishness off the start gets better when it warms up. At times when it is acting sluggish, it will suddenly jump forward as if a stuck/clogged valve opened up.

Is this a standard torque converter slipping problem and i need a rebuild or is their a easy/cheap remedy?

thanks
Dave