Realistically it was never a recall because very few failed under warranty. Obviously they figured out that they broke, but it's not uncommon to still see cars with original guides that still run OK, and they did take care of it, so out of 11 years of the VH engine in the Q45 only 3 model years were affected, so overall it's not that bad IMO.
I think it's kind of a luck thing. What happens is the pieces of the chain guides get stuck in the chain and derail the chain from the cam sprocket. I've seen chain guides that have broke clean off and fallen down into the oil pan, and the car is still running fine.
Not to mention, the chain guides cost about the same amount to do as a timing belt on a 1UZ, and you only have to do it once in it's lifetime versus every 60-100k, so overall I think Nissan was better by using the chain..
I think the first thing to do is check the injector resistance like Brett said. Running fuel injector cleaner or the "Italian tune up" won't really fix the injectors. If it turns out that more than one injector is bad, I'd recommend replacing them all with the phase 2 injectors (from a 94+). I'll wager one of Bret's beers that you have at least 2 bad injectors.
To be as practical as possible, you're most likely looking at replacing all 8 injectors, all the under plenum hoses, and probably the knock sensors (since you'll be in there).. That's at least a $1000 job there if you can DIY and find parts cheap.