Sorry you are having this trouble. Can you explain the hard to start problem in more detail so we can determine if it is a tune-up related issue or an electrical issue? You stated it is trying to start but not completely turning over. So there is an electric starter motor that spins the engine while you hold the key to the (start) position; 1, does this starter sound similar each time or sometimes faster and sometimes slower? If it sounds similar each time and like it spins the engine without struggling, then you likely have a tune-up issue like @Bassman eluded to. The throttle body, which is an air valve controlled by your gas pedal and the computer, lets enough air into the engine for it to start properly and not stall. This part gets dirty with carbon deposits over time and malfunctions creating a hard to start , low idle, and occasionally a stalling problem. The fix is to have it cleaned and perform an idle relearn procedure.
If the starter spinning is inconsistent and sometimes weak or slow, then that will be an electrical issue most likely. Let us know, and after you get this resolved, show the dealer service manager your receipt and ask for a refund on at least the labor part of that wire harness work.
If the starter spinning is inconsistent and sometimes weak or slow, then that will be an electrical issue most likely. Let us know, and after you get this resolved, show the dealer service manager your receipt and ask for a refund on at least the labor part of that wire harness work.