Engine torque regulation

[dawsy 22]

Hi all having had a good lexia session on my 2.2 2001 C5 and having replaced the MAF my C5 is like a new car {well new to me}it has power again and i can get up hills without much use of the gearbox the only fault that comes up and puts the car into limp mode, is temp fault engine torque regulation does anybody have any pointers as to what causes this fault and how to rectify it,any help would be much appreciated