I'll try to explain this problem as clearly as possible. I have a 97 Bonneville, automatic transmission.
When accelerating from idle, sometimes two strange things happen: the car reaches ~20 mph, and then does not go any faster even when feeding it more gas. It just reaches 3000rpm and does not shift to second gear. Also, the spedometer stays at 0mph. It does not reflect the speed whatsoever.
What tends to happen after this occurs, is after some short but disconcerting amount of time, the car actually shifts to second, the spedometer moves to the right position, and everything is fine after that. After returning to first gear, this problem may or may not occur again.
I only have encountered this problem when going from first to second. And, initially I thought it was only happening when the engine was cold, but its started happening more and more now, even when the engine has been running for a good while.
So, transmissions messed up? What should I do here?