Water Pump change,now engine light
 

so I just replaced my water pump on my 01 proto 1.6. As I was driving to work CEL came on. So I parked, unplugged my battery for a bit and so far its stayed off, any idea what could have caused it? Air in the cooling? the new pump simply being "new?" any suggestions would help, thanks.

The first thought I had was air in the cooling - letting the coolant temp sensor get hot or something. Did you read the code? - if it doesn't come back i'd bet there was an air bubble and it's now gone.
Another option is if you forgot to plug something back in, though that should re-log the CEL pretty quick.

turns out a hose that seemed to be connected my EGR above got knocked loose, all better now

good news - glad it was an easy fix.