Well I recently had a problem with my momo racing wheel with the center going to left or right after a few mins. this was without heavy driving, just smooth oval racing. If you have this problem then this might help, especially if you have tried the wingman team utility for the momo center fix with no success.
I dont have any detailed pictures so ill try my best to decribe it
. if you have opened up your wheel before then there is a good chance that that is whats causing your off center steering as debris could have gone into an important part. the back end of the motor in the wheel has 2 small black gears-one big and one small. You will notice that the larger gear has many tiny open spaces around it. you might have to open your wheel to know what im talking about. now on both sides of that gear are sensors, and they read every open space in that gear so they can see what position the wheel is in. This is just my educated guess, i dont know for sure. in my case, i found some kind of debris inside one of those spaces, causing the sensors to skip that position. Every time that blocked space passes the sensors, your losing a little bit of your wheel position, causing the off-centering after a few minutes.
All you have to do is remove the motor mount from the base and remove that important gear and clean it thoroughly. there are also two plugs that must be removed from the mainboard to allow the motor to come out freely. that should fix your problem
If you are having trouble taking apart your wheel, check out the site for help
http://web.axelero.hu/mozso/momo_e1.html
This may not work for everyone, but its here for the people who need it. Here is a pic showing the small gear im talking about... if anyone has this problem then try this tip. It worked for me anyway
i can try to describe in more detail if anyone needs me to.