Just yesterday afternoon, I was driving home from school, and while idling at a light, the engine began to sort of "rock" around like maybe a plug was misfiring or something... The next time I drove, it came and went...and now I just drove home across town, and it's "rocking" the whole way.

FYI:

I changed the oil last weekend, but everything went well
My MAF screwed up a little while ago, but that's fixed.
I also am waiting for a new 02 sensor, but that really doesn't explain this, I don't think

- do you guys think it might just be a bag plug, or an injector - (though I doubt this because the engine will rev up fine). I don't really notice a loss of power either.

Any suggestions?

 

Check your plugs, wires, etc. Does the idle speed drop and if so, how much? If you are unfortunate, could be a fuel injector.

Not sure if it would apply to this situation, but maybe a coil pack?

 

yeah check the basics first (plugs, fuel, air filter, and wires). it very well could be a bad injector too, but look at all the plugs and wire first cause the insulation on one or more of the plugs may be cracked and allowing the spark to arc to the intake or something like that. good luck

 

nah, he's got a VG only 1 coil.
injectors are unfortunately an all too common occurence on these cars

I sell injectors

 

The Nissan users handbook suggests maintenance, periodically. But oldies need some extra care on top of mentioned issues. Like groundings... or connectors cleanup: http://www.cardomain.com/memberpage/748507/14