Just purchased 2007 Sunsport 20V and the Center display is not working, any ideas on how to trouble shoot this? Also the engine will only get to 4000 rpms and then bounce between 3800 and 4000. the center display did not work but it just started the hesitation. I have changed the fuel filter, fuel pump, plug wires, plugs, and distributer cap. It is like there is a rev limiter on the engine. Thanks in advance for any help.