Volvo: volvo v40 gdi engine, mitsubishi gdi engine, volvo v40

Question
Hi, we have a v40 with mitsubishi gdi engine. it wont rev above 4,000rpm. we have have replaced throttle body and given it full decoke, but this has made no difference. no fault codes listed. can you help.

Answer
Sean,
Here in the United States we do not have the same engines. Using some basics make sure the timing is correct and that the fuel pressure is also correct. I know there is possibly not a setting for the timing but is the belt on in the right position? Things like intercooler hoses and air intake hoses all tight and not broken, loose clamps split hose to the IAC motor crack in the intercooler.