Logitech deiving force not working as it should

Okay. So i got an old Logitech Driving Force (ps2), it has an usb so it works perfectly fine on PC in general and in other games i play on the PC. I just bought Forza 4, and when i tried to play with my steering wheel, something was wrong. When i was using maximum gas on the gas pedal, it was just the half of the thrust that came out in the game. So i would only get the Audi TT up in 3rd gear. But when i pressed W on the keyboard the gas would work fine. So i tried to switch the gas to one of the buttons on the steering wheel, but same problem, so i know it is not the pedal that is the problem, it is something with the whole thing. But steering works fine, such as breaking. I tried to find drivers and download, but not helping. What can i do? Need help!

It does sound like you have to un-tick the ‘Pedals report as combined’ box in the device settings/Advanced for your Logitech Controller, you can get to it either via Windows Control Panel or through Logitech Gaming Software if this is installed.