Need for speed the run Car gear change/acceleration problem

Hi

 When I change the setting to Manual transmission the gears sometimes change up but I still cannot get over about100mph.

I have restarted the race and done everything possible and also cannot see anywhere if I have pressed a button by mistake. I went into the garage to see if changing the car would help but no its still the same. 

I have also removed the disk and tried Hot Pursuit and its exactly the same the cars simply wont accelerate past 45/50mph.