Car would not accelerate past 30 or 31 MPH no matter how hard gas pedal was engaged. The RPMs increase, acknowledging the gas, but the speed stays the same. Stopping the vehicle and putting in park dsnât fix it. This is particularly dangerous when going from city street to highway or interstate driving. It eventually self-corrects after about 5 minutes. Weâve experienced multiple instances now, and all have been in cold weather (<10° F).