dalejrroks

Ok so I have read as many of the posts I can find on here with the problems I am having but nothing has fixed the issues completely. My 06 MDX starting running rough and spit out codes of misfires, random misfires, and a battery low voltage code. I have adjusted the valves twice to be sure they are correct. Took it for a test drive and all seemed to be well and just before I got home it about died and wouldn't go over 10 MPH. I have checked all the coils. I have checked all the spark plugs. I have cleaned and tested the EGR system and valve. I have checked the timing through the 2 sight windows. Checked all the fuses. Yet when at idle i runs smooth but if you try to drive it or rev it up and the tac hits 2500 rpms it will misfire like crazy and again will not go over like 10 MPH and no codes show up now. I am at a loss now on what to do next. I am not the kinda of guy that will just throw parts at something I would rather find the problem and then fix it. I thought maybe it went into limp mode and so I double checked everything and pulled battery terminals and let it set over night with no change. I don't want to get rid of it since it is rust free even though it has 340,000. Not sure if the motor actually has that on it or not since I bought it used. So any help would be greatly appreciated.