Problem shifting with rear Altus derailleur
Bike is a 2003 Gary Fisher Advance. I recently removed the front derailleur since the bike is used 100% on the street (I just leave it in the 48 tooth chain ring) and that derailleur was rubbing badly on that chain ring. In order to do, I of course had to remove the chain and as a result I decided to remove and clean the rear derailleur which was very 'gunked' up (it hadn't been cleaned since, well never).
Now with everything put back together, I am having some difficulty with the shifts. After using Sheldon's site, I have adjusted the high and low limits properly, but can't seem to make the index adjustments precise. Perhaps it goes beyond the adjustments? Here is the issue... when shifting from 2-3 on the rear cogs, nothing happens. When I shift from 3-4, it either shifts into 3rd or goes directly from 2-4. Everything other gear shifts perfectly fine. What do you think? I couldn't seem to find a decent answer to this specific issue by searching.
Thanks in advance.