amowbs

I have a 90 300TE that is having trouble passing GA emmissions. The HC and CO #s are almost nonexistent while the NOx #s are through the roof. I have swapped out or replaced many various parts with no change. It seems that the car seems to starve for fuel under load. It runs great other than the emmissions problem. Any suggestions would be appreciated.
Parts that have been replaced:
Fuel pumps, Fuel ECM, OV relay, Cap, Rotor, Plugs, EGR valve, EGR tube, Ignition Module, O2 sensor, Injectors, Fuel Distributor, and MAS.