Engine/Transmission (1998.5 - 2002) Codes 236 & 238-What now?

[BBoyle]

1999 with 222K, exhaust manifold cracked, got new one, but before I could install it, the check engine light came on with codes 236 & 238. Manual says this means high voltage to MAP. Replaced manifold, still same codes. Truck will still run 75 mph, but takes awhile to get there. Acceleration way off. Every once in a while, will accelerate normally. Changed fuel filter (just in case), have good fuel pressure, checked connection at MAP, tightened all inter-cooler and turbo boots, and checked waste rod. I had to free it up, but still same condition. Any suggestions ?