Looks like 2 coils which should maybe move in tandem but don't

Right side of window has a coil system. Window won't open unless I use tilting function, tip window out and then move it and replace tilting lock. Won't stay open on it's own sometimes and doesn't glide smoothly. Makes a cracking sound when I close it. Left side of window seems ok.

Thanks for your patience. I took the entire bottom portion of the window out and here are the pix. The bottom portion of the window has nothing on either side except a metal hook type bar sticking out on the bottom on both sides of the window. Accross the top is the locking mechanism which allows the tilt out. 

After I removed the entire bottom portion I was no longer able to re-insert as there was some spring action that moved a piece upward and I could not reposition it lower to insert the window back into the track. Make sense? Thanks so much for your help.