Timing off?

[qeg84doa]

Hi all. Have a question someone in here may be able to answer. I am currently working on a friends 2008 Aveo. It runs decent but idles like crap. Ive changed the spark plugs, coil, intake hose( had a crack in it). Nothing helped. I then decided to check to see if the timing marks are aligned. It looks like it's off a tooth. Can someone verify? Thanks in advance. Also, if it's off by one tooth, how difficult to get it back in time?