2003 Chevrolet Suburban P1516 help

Hi, My truck is a 2003 Chevrolet Suburban 1500 5.3L v8. My problem is every morning when the engine is cold I get a "reduce engine power". Pulled out the code and got 1 code which is p1516. What I did is cleaned the TB, cleaned the MAF, changed the TB connector and passenger side engine ground wire and still does it every morning or when the engine is cold. When cold though when I first start it and revved the engine a couple of times no "reduce engine power" but when I let it idle during a cold engine without revving it I get the "REP" and code p1516. One morning I tried disconnecting the plug to the MAF and w/o revving everything ran fine, No "R.E.D". Tried it a couple of times and no R.E.D. Though the code for faulty maf pops up but no R.E.D. What gives? When engine is warm everything is normal.