Ford Repair: Check Engine Light, leaky hose, auto zone

Question
I have a check engine light on. I have replaced the coolent temperature sensor and this http://www.niehoff.com/catalogs/nie_bgbulk.aspx and it is still on.  My car will cut out if I change gears in slowing down or speeding up.  Also, when sitting at a light.  But always I shut it off and turn back on and it always starts and seems fine.  

The idle goes up and down.

Any ideas?

Answer
mary
what led to the coolant sensor in the first place and what kind of car is it? have you had a scan done on it i know advance and auto zone scans
them for free but they don't actually test anything for example you take your car get it scanned and you get a coolant sensor fault code they most times will tell you that your sensor is bad and you need one when another cause like low on coolant because of a leaky hose or water pump etc. is bad you can get a coolant sensor fault code then also. dirty or   loose connections can also give you that code. i am not in any way saying don't have them scan your car but if they do have it checked before just buying a part.