That's most likely your problem right there tellan. I'm using Huffyuv in Premiere Pro without problems. My settings for the Huffyuv codec are Predict Median (YUY2), Predict Gradient (RGB), field threshold 240 lines, and I have "Always suggest RGB format" checked and "Enable full-size output buffer" checked.
If you change your settings, you might have to recapture in order to make your AVI's work in Premiere.