Alan,

I recently had a condition with my 84 GL where my mileage was down around 11 mpg. The exhaust was intermitently black and I could feel the power drop at the same time.  I replaced the temp sender for the injection to no avail.  A friend suggested that I look at the Ox sensor as the next most probable problem.  I had discounted that because it was fairly new.  I did however examine the wire and as a matter of course, unpluged and re-pluged it in the engine compartment.  The problem was fixed.  No more smoke and my mileage went back up to 21 mpg.

Walt Spak
Pittsburgh, PA.
wnsopc3@3rdm.net