Idles extremely rough and blows black exhaust and will not idle on its own

No! No way!

Thank you for replying Kin Chan. Why is it that I can not just replace the defective Mass Air Flow Sensor when my current Throttle Body Assembly isn't defective, and the only thing defective is the Mass Air Flow Sensor? Also it would seem like it would be a lot more involved to replace the entire throttle body then to just remove the electrical harness, and two screws that hold the mass air flow sensor to the throttle body. Please explain. Thank you again for replying.

That mid late 1990's MAF from Nissan has so many versions is 1 of the Nissan intermediate model change disaster. Nissan had it build all together as a unit. We tried about 3 or 4 fr after market. All has different value under a load and I know if you are not getting it from Nissan as 1 piece any other aftermarket is a guess at the best. It is a high dollar items. We had to use a scope and a simulator to catch the problem before we are completely sure to tell the customer. That's why I am so sure on your case possible and probable. Less you are sure all signal power/ground and ref voltage existence. How to do it or what to use is mechanic. If your dealer put it in writing that is the problem. Let em fix it and back it up if it doesn't work. Then don't pay them. That's why average owner don't want to circumvent and do it yourself. If the price is too high for your budget then it is financial.