Ranger stumbles 4.0

Just had to replace intake manifold gasket due to coolant leak. That wen t well, but now the engne stumbles coming off idle. I've double checked all plugs and connectors. Fuel pressure is right on. truck runs smoothly and has decent power, however, it really stumbles badly coming off idle, especiallyt if you tromp it. If you press throttle smooth and gentle, everything is fine. I have an Actron scanner and monitored engine parameters. Timing is about 22 btdc at ide, and drops off to about 6 when accellerating, it then comes back up to about 16 with the throttle floored. Seemed normal to me. TPS looks good throughout its range. This does have the cam position sensor, which I removed and reinstalled using the Ford tool.
I don't know if it's the scanner or actual, but scanner says all fuel trims at -100, and all O2 sensors show no voltage. But the fuel system is in closed loop. Any ideas or help would be greatly appreciated.
97 for Ranger, 4.0