P0101 code on a 1999 Jetta TDI, sluggish, CEL showing

My CEL recently went on and at about the same time, my jetta started acting sluggish when excellerating. There is some hesitation when first taking off , as well. Having owned a TDI before, I figured it was the MAF and replaced it,but still sluggish. However, the after market MAF doesn't "snap" onto the connector like the old one. I used some duct tape to get a snug fit, but no difference. I discussed this with Dealer , and they said that connector could be bad, and that I should have bought VW parts (from them) so they would fit! Any thoughts out there? The OBD code lists Vaccum hose, throttle body intake and BARO/MAP as also possible sources of this problem....