I have a 1998 Pontiac Firebird 3.8L.
The first problem I have is that I have a code thrown. I checked it, it's a P0125 "Insufficient Coolant Temp for Closed Loop Fuel Control." Can anyone translate that for me...

What do you think the fix is?
Also, has anyone ever changed the plugs on this model? I tried to do it the other day, the plugs are really wedged up in their and I was unable to reach them. Any tips? Is there anything I need to take off to get to them?
Any help on either problem would be greatly appreciated.