08 automatic shift problems
Look up A6 shifting problems, this is a fairly common issue with the 07's as well. Mine started doing that after about 1000 miles too. Basically you're loosing 1st gear.
here's a couple links.
http://forums.corvetteforum.com/show...light=shifting
http://forums.corvetteforum.com/show...light=shifting
http://forums.corvetteforum.com/show...light=shifting
Last edited by Atomic-Vette; Dec 17, 2007 at 10:06 AM.


I took the car into the dealership last week as I was having a TCM problem where it was erroneously setting a trouble code and putting the car into limp mode. The dealership reprogrammed the TCM and although it did fix the problem with the trouble code, the car started feeling like it was losing power every time it shifted (the car's an automatic).
At first I thought it might have been due to the adaptive learning of the transmission being reset while at the dealership but after three or four days of aggressive driving (in hopes of relearning the TCM) it didn't help any.
I hooked up the scanner on Saturday night and discovered that my spark advance was dropping up to 30 degrees between each and every upshift. I did some more research and found out that TM had been enabled in the car, hence the feeling like I was losing power.
I know that TM has always been present in the A6 transmission but I'm pretty sure that having it enabled during an upshift is new because my car never did this before I took it in last week. Fortunately for me I own an HP Tuner so I was able to disable the upshift TM but I wonder what would have happened if I didn't own one.
As such, if you get your car back and it suddenly starts feeling funny while shifting, that'll most likely be the reason why.
I took the car into the dealership last week as I was having a TCM problem where it was erroneously setting a trouble code and putting the car into limp mode. The dealership reprogrammed the TCM and although it did fix the problem with the trouble code, the car started feeling like it was losing power every time it shifted (the car's an automatic).
At first I thought it might have been due to the adaptive learning of the transmission being reset while at the dealership but after three or four days of aggressive driving (in hopes of relearning the TCM) it didn't help any.
I hooked up the scanner on Saturday night and discovered that my spark advance was dropping up to 30 degrees between each and every upshift. I did some more research and found out that TM had been enabled in the car, hence the feeling like I was losing power.
I know that TM has always been present in the A6 transmission but I'm pretty sure that having it enabled during an upshift is new because my car never did this before I took it in last week. Fortunately for me I own an HP Tuner so I was able to disable the upshift TM but I wonder what would have happened if I didn't own one.
As such, if you get your car back and it suddenly starts feeling funny while shifting, that'll most likely be the reason why.


I went back and checked several earlier scans I did on the car when I was first tuning it and saw absolutely no evidence of any TM during upshifts so it has to be a recent TCM programming change. I'm really surprised that more people aren't complaining about it.
I forgot to mention that there were a couple of other additions regarding this as well. There's also a TM setting for CT (closed throttle) downshift as well as a "Garage shift" (whatever that is). There's a fourth one too but I don't have the software installed on this PC so I can't remember exactly what the last one is.






