Hi all

i have 2001 audi a3 1.8t sport. been good car for last 5 years, untill recently engine management light stays on, the car intermittantly looses power for about 2-4 seconds then power comes back, using more fuel and sometimes revs go up and down.
have had the m.a.f sensor replaced which cured for 2 weeks. hoses have all been tested no leaks found. checked diverter valve all o.k.
fault codes are 17704 and 17705.

any advise welcome as had the fault for year now.