I HAVE A '04 9-3 ARC. I paid for and installed( 10 installtion of these things on previously owned cars) an k&n open air filter that replaces the intake tube and filter vs. the old box and paper filter. Everything was fine, a little extra noise(wife hates it), turbo spools up quicker also. After my wife driving it for two days the check engine light comes on, never had a problem with this car ever. A day later she was out on the highway, going about 70, pulls on the off ramp, stops at a light, pulls off, the car would not go over 15 miles an hour till about third gear(she was freaked out because she pulled out expecting the power to whip about and almost got hit) . Have had it checked(Saab Dealer), trouble code cleared(mass air flow sensor, had it checked and cleaned, it was fine), they had no idea what the problem was and of course the car didnt act like that for them.Ive pulled it off then replaced it two times, still the same problem, no power till about third gear. Any suggestion before my wife forces me to take it off, also she is driving my suburban, it would be nice to have it back.