Celica Forums General Discussion Engine and Performance 6th Gen Cabrio High Idle

First post here, I can't seem to find anything online about my exact issue so I'm trying here.

Background info: 2lr 6th gen Cabrio 1996.

When I start up cold, it likes to sit around 2000rpm, it really struggles to warm up until I'm sitting in traffic 15 minutes after I start. When hot it sits somewhere below 1000, somewhere around 750 and hunts like it's trying not to stall.
If I go straight to highway driving it never warms up. (Temp gauge still below bottom)

When driving while cold and lifting off the gas pedal it judders like it's about to stall, even at like 70mph and 3000rpm.

My guess is it's running rich because the engine thinks it needs to "choke" itself but I have no idea if I'm even correct, or where to start if I am right.

All help and suggestions is welcomed, thanks in advance.