Nissan Forum - Nissan Enthusiast Forums - 2012 Quest, Rough Idle, Specific Symptoms, HELP!!!

So for a few weeks now my 2012 Quest [82K miles] has had a rough idle. The first time it happened I had been sitting at a particularly long traffic light when all of the sudden my engine started rumbling and shaking a little followed by the check engine light coming on. I took it to an auto parts store and had them check the code which came up as P0101 MAF/VAF Circuit Range/Perf Problem. After looking that up I found that that code could be for any number of things. The most common was the mass airflow sensor. I replaced that and though I think the engine is in general a little quieter [maybe just my imagination] it didn't fix the problem. The rough idle is not all the time but sporadic. It happens when in park or stopped idling. It seems to be a little worse when in gear. As soon as I take my foot off the break and give it even a drop of gas it stops instantly. I've noticed that when it happens the RMPs drop. It usually hovers between 700-1000 when idling but when it rumbles it drops to 350-500, the lower the move violent the shaking is. It usually only last a few seconds and then returns to normal. On my Father In-law's suggestion I tested for a vacuum seal leak by spraying them with WD40 while the engine was running to see if the engine sound changed if it sucked some in. I didn't notice anything like that. From what I have now read, it could be spark plugs, MAP sensor, O2 sensor in the exhaust, clogged fuel injector, etc. ect. If anyone can help me narrow down the possible culprit I would really appreciate it.

There is also another issue I am having that I will post on another thread. It seems unrelated but with computer controlled cars, who the hell knows. If you have the time please check that thread too.