where's the maf ground?

[captainspectacular]

Sorry if this is a stupid question....a few months ago i dropped a relatively "new" KA (45k) in my 91 240. For the last month or so, my idle has been getting progressively worse. When I start it up, it'll bounce around between 300 and 1000 till it's heated up, then it sits around 900. I pulled the spark plugs-they had lots of carbon buildup, so i figure it's running rich. I checked all the wiring harnesses again, and they're all tight. My next guess was the maf ground, but i can't decipher the wiring diagram in my chilton's book. Where's it at? Also, i've got an aftermarket air intake that didn't have the hose fitting for the extra air chamber about halfway to the throttle body; since it didn't go anywhere, i figured the car wouldn't miss it. Could that also be my problem? Thanks alot!

[captainspectacular]

sorry for the redundant post guys... I just read through kirk's ordeal with his idle; that gives me plenty to work with! I'm still wondering if that little "apendix" on the air intake's necessary though...