Engine Running sluggish

Hey everyone, just looking for some ideas on What to check next. I have a 93 5.0 lx, mass air, meter, 70mm throttle body, cold air intake. Nothing to major just bolt on stuff. Car had been sitting up for a while, i cranked it and let it run every 2 to 3 months. Started back working on it a couple months ago. Had an idle issue and got that taken care of but it still is feeling sluggish. I have smoke tested it and everything seems fine with the vacuum hoses. Was thinking about changing out the coil and distributor cap, figured i would ask here and see what else to check. I have ran the codes and with it running it kicks out O2 sensor. Im thinking its doing that because i dont have the ones in it after the Catalytic converters (was no place for them when i installed the xpipes 15 years ago. Lol) but i could be wrong about that also idk? any help would be appreciated.
 
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When you say 70mm throttle body and a cold air intake, nothing too major just bolt ons what do you mean?
That code could mean a couple things, low voltage at the 02s or low fuel pressure.
I would start with a fuel pressure check, or if you really want to learn what is wrong with your car go here:
 
I mean that to my recollection the throttle body and cold air intake are the only things done to the engine, by nothing major i mean ive never had the engine apart or added anything else to it just those first basic mods you tend to see. and other than those it has equal length headers, xpipes and flowmasters is all that has been done to it. I fogot to mention i have checked the fuel pressure with the car off it was at 37
 
OBD II added the post cat O2 sensors to check how the cars are working. The EEC IV on the 93 Mustang is still OBD 1.
How about you post the actual codes, then we know what the computer is really saying, and you can search for posts with the same codes. There is likely to be a repair procedure for them on here.

It does have the 2 upstream. i know a lot of cars have 2 after the cats wasnt really sure if 5.0's were supposed to or not. just kinda 2assumed it was supposed to have 4 and didnt.