407 1.6hdi does not exceed 120 km speed

slm friends today i realized that the problem is comfortably 120km speed, but after 120, it does not eat gas, it does tearing & nbsp; this problem was so damn & nbsp; what could have happened before & nbsp; I look forward to your help, if any.

Have a software limitation?

I'm not sure, but there may be a map sensor error.