non A-body question, PT -03 trouble

Been struggling with an issue on our PT Cruiser.
It got a bad missfire from time to time when warm.
Have turned the ignition key on and off three times to get any fault code but says "done".
Today when going to the store I put the gaspedal to the floor but it stopped revving at 4k rpm (even though I kept the pedal to the floor, with the gear in Park) and acted just like a rev limiter stepped in.
Any help on ideas is very appreciated, haven´t replaced any item yet since I don´t want to throw money at the car.