Also check the adjustment on your rear drums. I swore I had the same issue - somehow I got air into the HCU while replacing my front brakes, even though I didn't replace the calipers or disconnect the hoses - and when I took it to a shop to have them rebleed for me with a scan tool the guy told me that my rears were "way out of adjustment" and that that was most of my problem. D'oh!

So I guess sometime after it warms up I will have to tear into the rear brakes to make sure that the self adjusters are working correctly and repair/replace as necessary