Low, rough and surging Idle

When started cold My car DOHC Duratec engine surges between 900 and 1200 rpm, when it warms up the idle sits at about 500-600 rpm. If you slowly apply gas it shutters and the rpm's drop, sometimes it recovers and runs okay above 900 rpm and sometimes it stalls.I had Auto zone put the computer on it and received codes, P0174, P0113, P0102, P0193, Pp0171, P1504, P0156, P1131 and P1151 with a recommendation to change the PCV valve. Thought it to be a long shot but changed it and it did help a little. I have gone over the vacuum lines and can not find anything obvious. I did a check of the MAF and found power and ground where it should be and during the "signal" check found 0.5 volts as a base voltage and when accelerated the voltage fluctuates between the 0.5 volts and 0.7 volts. There is no obvious visual damage to the catalytic converter, and the exhaust does not seem restricted.
The car runs like a champ above 900 rpm, if at a stop, maintaining 900-1000 rpm the car is fine, if allowed to start from a stop at the 500-600 rpm at normal acceleration, the car shutters, hesitates and then takes off, or stalls, but once over 900 rpm it again runs like a champ!
I am suspect of the MAF as the "signal" test should have rising voltage when accelerated, but it was changed six months ago along with wires and plugs for the same type of symptoms and has been running fine. Wondering the MAF could be the issue or if something else can cause the "signal test to fail, and/or can it be a fuel pump putting out low fuel pressure. I do not have a gauge to test the fuel pressure so have not done that yet.
Any suggestions or help is greatly appreciated I do not just want to start shotgunning parts.