Okay so for starters I have a 2005 350z convertible. Im having a serious issue and the dealer quoted me $2400 TO FIX. I don't believe its that much out of pocket but maybe for them to do it so here we go. I purchased this car around 5 months ago I brought it home it needed a battery. My little brother loves cars so I figured it would be a start to letting him work on my car (hes 9) . Went to the store bought a battery and let him hook it up well, little did I know I bought the wrong sided post and the battery was hooked up wrong!!!! I know I know save it haha. So I fried the alternator I replaced that and seem to be running okay for a bit. Than the car started to not like being started it wouldnt't turn over. I turned the key a few times and it would fire. It did this for a bit than it started o start in a limp mode with the check engine light on the slip light and vdc light all on not reving above 1500 rpm. So I brought it to my mechanic he replaced the throttle body hes drove it around for a bit I get the car runs fine think all is good I park it for the night. I go to start it again and its in limp mode!!! I bring it to the dealer they tell me they found a "few wires leaving the throttle body that the pins weren't seated They also said they ran it through a bunch of tests through the computer soo im at a loss. I checked all the fuses several times. Every last fuse so this leads me to believe the ecu??? So again drives fine home, next morning in limp mode again!!!! with all the lights on. I need help here guys I need this car to run right!!!! So my thought is that the ecu is fried or at least something in it. All because big brother let his little brother try hooking up a battery! Help me here guys im brand new to the forum and have no where else to turn!!