Audi 80, Idle Blues, Need Help

Hello Audi fans, I have a 1991 Audi 80, 1800, with mono-jetronic fuel injection system. The problem manifested itself when i realised that i had a fuel leak from the fuel filter. I repaired the leak, then i discovered that the flange between the throttle body and intake manifold was not only split, but almost severed. I instantly replaced that too. Upon making these repairs, I now have a problem of the engine idle being very lumpy, and a strong smell of petrol, from the exhaust once the engine has warmed up. It is fine when the engine is cold. I understand you can reset the memory of the control unit? I assume that the injection unit, tried to compensate for the extra air intake, at the time, now the problems have been fixed, it still has the previous information stored in memory? am i right? how can i reset the memory? where is the control unit? do i need any special tools? i am use to turning a mixture screw, to adjust the settings, now i am stuck, and dont fancy entrusting an Audi dealer to carry out the diagnostic repairs for a major fortune. Help Help Help. I can give you as much information as you need, should you need it... Yours Hopefully Hady.....