04 X5 4.4i a few issues Im trying to work out...Need Help!

[Johnny_5]

Got the smoking at idle and all the oil and power steering leaks figured out but now I'm getting a P2184 Engine Coolant Temperature Sensor 2 Circuit Low Service Engine Light and Hard shifting from a stop or slow moving traffic!?!

While working on other things I accidently pulled the Coolant Sensor on the lower radiator hose while working on a few other things but I put it back in but lost a bit of coolant so I topped it off and thought I was good until I drove the car most of all day yesterday and noticed that kept coming on. I don't see any leaks and will double check to make sure its plugged in securely but I'm just wondering if I need to bleed the system? Once I delete the code I can drive fine no issues but eventually it comes back?

Second issue I noticed when I come to a stop or slowing down in traffic and when I start to accelerate if I go a little to fast it shifts extremely hard only in 1st gear. So I've been extremely careful while accelerating and go extremely slow at first. This doesn't seem right? Also during acceleration its very slow but once again I'm not accelerating like I usually would due to the hard shifting / clunking I get!

Yesterday has been the first day I've driven it all day since I purchased this car so I cant really say how it was before and after.

Any help would be grateful!