The original Greek translations below are transliteral. [...] is a replacement for "Jesus said" or "Jesus answered" etc.
Greek: Why me sayest thou good? No one good except one, God. KJV: Why callest thou me good? none is good, save one, that is, God. NIV: Why do you call me good? [...] No one is good - except God alone. NRSV: Why do you call me good? No one is good but God alone." Mark 10:18 Greek: Why me callest thou good? No one good except one, God. KJV: Why callest me thou good? There is none good but one, that is, God. NIV: Why do you call me good? [...] No one is good - except God alone. NRSV: Why do you call me good? No one is good but God alone. So far so good. Some minor changes but nothing that is really objectionable. Matthew 19:17 Greek: Why me questionest thou concerning the good? one is the good KJV: Why callest thou me good? There is none good but one, that is, God. NIV: Why do you ask me about what is good? [...] There is only One who is good. NRSV: Why do you ask me about what is good? There is only one who is good.The NIV and NRSV are reasonably good translations in all three passages. Minor changes but mostly honest attempts to make the passage readable to a modern English-speaking reader. However, if we look carefully at the original Greek manuscripts for Matthew we notice that it does _not_ include the mention of God at the end of the statement. The additional observation that the actual Greek words used are not the same in Matthew as in Luke and Mark eliminates the possibility that Matthew's Greek simply omitted the word (by accident, perhaps) at the end (it differs throughout).
In spite of this, Matthew in the KJV is all but identical to Luke and Mark ("me thou" as opposed to "thou me" etc.). The monk who wrote the passage in Matthew for the KJV obviously ignored what was in front of him (in Greek) and chose to simply use the Mark/Luke passage because he had noticed the inconsistency. The KJV was the only English translation of the NT for over 300 years. The KJV was the accepted translation during the birth of fundamentalism and it contains this and numerous other inconsistencies.
This particular inconsistency is not of great importance theologically and carries no great weight of its own importance. However, there are 147 others in the NT alone that I have found (and probably other instances that have been found by others). The net result is an overwhelming body of evidence that indicates intentional editing and tampering in an attempt to remove inconsistencies in the KJV.
A large element of the NT is a deliberate attempt to deceive. This book (the Holy Bible) cannot be trusted. The really astounding thing is that the translators missed some big, obvious errors and yet took the time to 'fix' some small technical ones.
I am in the midst of compiling my findings into a book that I hope to publish that will show not simply that there are errors in the bible but that there has been a concerted effort made by translators to eliminate these errors. In short fraud and deceit.