Just happened two days ago, my car will not go faster then 35 mph without the RPM's raising to 4. There was a bad cell with the battery going to the alternator and that was replaced(battery)that took care of the engine light. Two different service places are still unable to fix this limp in mode.
Limp in mode on 2008 Chrysler Pacifica
You need to get your car to a service facility that has the ability to reflash (reset) the electronic control module (ECM). It sounds like the ECM is 'stuck' in this mode and needs an attitude adjustment.