Re: Lost 1st gear...
Generally speaking, it has lost an input wire, I have found on my car the TPS reading is wrong and causes it to go to 'limp' mode, if it's not electrical could be the s5 solenoid (i think).
You have bands in the gearbox still, and in 3rd gear trying to move the car from stop will get the bands slipping, i.e. friction , so it can only get worse and worse and not good for the gearbox.
reset the computer, disconnect battrey for 1/2 hour or so, you have smartlock, so if car wont start when computer is reset, then leave ignition on for 20 minutes should solve that.
I did put something here, but it vanshied, I think
"So long and thanks for all the fish!"