Nissan Repair: 98 Maxima w/P0600 & P1605, computer link, jan jan

Question
Someone tried to change our manual over to A/T well when it wasn't successful we went back to 5 spd manual. The car once started runs perfect but it is hard to start and it has a P0600 now it has popped up w/another code of P1605 along w/ P0600. All modules have been plugged in we have checked everything the only other solution is we are wondering if he changed the computer back from auto to manual..he swears he did.  Would this be a problem with the starting.  We have reset the codes but they still come back on the car once cranked will run forever.  We are taking the ECM to dealer tomorrow to see if it is for a 97 A/T or 98 Manual.  We don;t have access to the other computer that it was switched with.  Would it run this good if it had the wrong computer. Also we can get the codes cleared but they still come back on after about 5 Minutes.  Do you have any ideas...we are baffled and frustrated.  thanks for any help.  Jan

Answer
Jan,

Both codes refer to computer link problems.  The first is the link and the second is the transmission data link.  I would think the ECM is the wrong one.  The car would run with the wrong computer but would freak, like it is doing, if the wrong computer, like a manual for an automatic were installed.