Smog issues in a 96 gas hummer in CA....help needed!

[Edward]

I was about to purchase a gas hummer from a guy locally until I noticed that he had failed his smog. Upon further investigation, this vehicle had failed smog once before and was labeled as a "Gross Pollutor" by CA DMV. The HC(Hydrocarbon) was at 157PPM and the max allowable is 150PPM. Although he only failed by 7PPM, it still worries me that he is that close to the max. I've been told that cars with repeated smog issues usually have serious engine problems. Does anyone have any helpful insight into this problem? Thanks
Edward