Did you “clear” the computers T/Cs? I have the same problem on an 88 IROC. The manuals that I have read claim that it may take some 40-min or 40 miles to show the T/Cs again. Also I have heard about sensor and other adjustments that will also give the same “code 34”. How much did you pay for the MAF sensor anyway? They want a mint for one in the Bay Area.
Mark (A.K.A. Z28 Mark)