I just fitted a stock 4ag 20Valve silvertop to my AW11. I'm running a stock ECU etc. It starts fine, idles fine, and runs fine until but seems to rev limit at 4500rpm. I know its got fuel and its not loosing power to the igniters of coil. Its as if something in the ECU is rev limiting it at 4500 rpm. I have the speed sensor connected and have no error codes on the check connector... ANY IDEAS ???????