Yes I have had code 0455 since I drove it the first time after the headgasket repair. Almost 4 months later it is still on.
I'm pretty sure the dealership did damage something to cause this ce to stay on all the time. The very first time I picked the car up antifreeze and oil were both running (not dripping) out of the bottom of the car. How could you miss something like that? Plus one time when I could barely get the car to run, a look under the hood revealed a couple of hoses that were off and some broken parts that I'm sure were caused by the original technician who did the headgasket repair. It appears to look like sloppy repair work to me, negligence for purposes of the court.
If you don't mind I am going to use parts of your explanation as a possible explanation why negligent repair work could cause the ce light to stay on and I am now experiencing driveability problems. Can't link the trans in any way huh? Is there a possibility it could be something other than the trans?
Thanks!!