I recently pulled the motor out of my 91 teg (B18A1) and after putting it back in I noticed that the it was not running right. while driving after the car was warm it would sometimes sputter and even stall. The ECU was flashing a code 43. I noticed on my air/fuel ratio guage that the car was running very lean and sometimes not even registering. I changed my fuel filter and it made no difference. I checked all the vacume hoses and they are all correct, all the electrical connections are conneceted properly (as far as i can tell). I checked my timing, that is fine. I have reset my ECU and none of this has made a difference. I was thinking that i have a ground problem since i made myself a temporary ground from the engine block to the firewall and that helped the car not to stall, but it still sputters when it is being bogged in the lower RPMS (1-2000 RPMS) and still registers as lean on the air fuel ratio guage. Also my CD player will randomly reset wiping out my presets and when the car is off the windows will not go down before the door is opened.

stock B18B1
Ram air intake
APC wires

I don't know what to try next Please help