I have had my new 07 back to the dealer 7 times for the same problem. If I set the cruise at 70 and try to go up a slight grade the speedo drops down 5 mph and feeds in no gas, then the car shifts down in SECOND and revs up to 76mph before it stops or you have to slam on the brake to get it to stop.
I told the zone rep that my 02 does not have this problem. He told me all 07 pt's do this and they will not fix it until they get enough complaints. they also said they can't fix it because it shows no codes.
This is a safety problem for my wife. HELP