If Pareve food was cooked in a meat pot must one wait six hours after eating it?
If Pareve food was cooked in a meat pot it is permitted to eat dairy products after eating that food without waiting at all. There is no custom to be stringent. [This applies even if the pot is Ben Yomo.]
If the pot was dirty with meaty leftovers: Even if the pot was not washed well and contained some leftover meat when the Pareve food was cooked inside it, one does not need to wait prior to eating milk products, although one may not eat this food with dairy products. [Some Poskim however rule that this only applies if the food contains 60x versus the meat, and there is no meat taste felt in the food. Other Poskim rule that this applies even if the food did not have 60x the meat. Even in their opinion however, this only applies if there is very small amount of meat fat or gravy in the food, while if there is a large amount, then one must wait six hours. Likewise, it only applies if one does not eat any actual meat. Likewise, this only applies if one did not intentionally leave the meat in the pot to be mixed with the Pareve food, however if one purposely did so then he needs to wait six hours. However, some Poskim are lenient even in the case that one intentionally added a small amount of meat. In all cases, one is to clean and wash his mouth prior to eating dairy.]
Pareve food that was cooked in a meat pot one does not need to wait six hours prior to eating dairy. This applies even if the pot contained a small amount of leftover meat gravy/fat, in which case although it may not be eaten together with dairy, one does not have to wait six hours. However, in such a case, one should clean and rinse his mouth prior to eating dairy. If the pot contained a large amount of meat gravy, or one ate actual pieces of meat, he must wait six hours.
If a dirty meat spoon was used to mix a Pareve food, must one wait six hours?
If one placed Pareve spaghetti in a pot that contains a small amount of meatball sauce, must he wait six hours?
 Rama 89/3; Drakei Moshe 89/6
 Pashut as otherwise there is no novelty in the Rama, and so is evident from Shach 89/19.
 Shach 89/19; Bach 89; Minchas Yaakov on Toras Chatas 77/13; Peri Chadash 89/19; Beir Heiytiv 89/11; Lechem Hapanim 89/24; Beis Lechem Yehuda 89/15; Orach Mishar on Darkei Moshe ibid, brought in Darkei Teshuvah 89/42; Zivcheiy Tzedek 89/36; P”M 89 S.D. 19; Pischeiy Teshuva 89/7; Chochmas Adam 40/13; Aruch Hashulchan 89/13; Kitzur Shulchan Aruch 46/10; Kaf Hachaim 89/59; Igros Moshe Y.D. 2/26; Kitzur Yalkut Yosef 89/37 [Yalkut Yosef p. 426]
Other Opinions: Some Poskim rule that if the pot had leftover meat, one is required to wait [a full 6 hours] prior to eating dairy. [Elya Raba O.C. 173/4; Elya Zuta 173/3]
 The reason: As since there is a very minute amount of meaty leftover inside, and one has no intent to eat and simply does not want to bother to clean it, therefore the Sages did not decree that one must wait six hours. [Yad Yehuda ibid, brought in Darkei Teshuvah ibid]
The proof: The Rama states
 Beis Lechem Yehuda 89/15; brought in Pischeiy Teshuvah and Darkei Teshuvah ibid; Megadim Chadashim 89/5; Yad Yehuda Pirush Haruch 89/5; Zivcheiy Tzedek 89/36; Ben Ish Chaiy Shelach 2/12 [rules to wait one hour if there isn’t 60x and one who waits 6 hours is blessed]; Kaf Hachaim 89/59
 Yad Avraham 89; Pischeiy Teshuva 89/7; Aruch Hashulchan 89/13
 The reason: As otherwise what would be the novelty of the ruling of the Rama. [ibid] As the entire issue of waiting six hours according to Ashkenazi ruling is a Minhag, and there is no custom to wait six hours after such a case. [Aruch Hashulchan ibid; See Darkei Moshe ibid]
 Orach Mishur ibid, and Yad Yehuda ibid, brought in Darkei Teshuavh; See there that it is implied that only when there remains a little bit of fat in the pot did the Shach/Bach rule that waiting is not required, while if there is a large amount of fat/gravy, or actual meat, then one must wait.
 So seems Pashut; See Darkei Teshuvah ibid
 Yad Yehuda ibid, brought in Darkei Teshuvah ibid
 Pischeiy Teshuvah ibid
 Ben Ish Chaiy ibid