Mechanical Problems & Technical Chat - Transmission, Reverse and 4th gear; 91 LX civic

I have a 91 Honda LX civic. The transmission is automatic. The car will be able shift into reverse at random times. It generally has more trouble in cold weather. It is also unable to go above 27mph in D4 when I accelerate above this is seems to lose grip on any gear and I'm unable to accelerate at all, but while in D3 I can travel above 27mph, and I usually try to go around 40mph to prevent the RPM's from going excessively high. Can anyone help diagnose this D4 and reverse problem?

Thanks for any help!!