2004 Dodge Stratus Stalls at 2500rpm

Thank you in advance for your help!
Our 2004 Dodge Stratus 2.4L DOHC recently had to have the whole engine head replaced due to bent valve that was caused by lack of oil pressure to the cams. The new head has been installed, along with brand new cam sensor, crank shaft sensor, and oil pressure sensor. The car runs now, but it will not rev over 2500rpm. Once the engine hits 2500rpm, the engine sputters and 'jumps'. I have taken this to a dealer & they said it was out of time. I had timing checked & it is timed perfectly. The dealer said the PCM is working fine. Do you know what could be causing this issue?