See my other post for background info:
http://www.sr20deforum.com/showthread.php?s=&threadid=16369

When the tow truck dropped if off it was running like crap so I checked the codes and got:
12 Mass airflow sensor/circut
14 Vehicle speed sensor
33 Oxygen Sensor

Then I started the car up later, warmed it up, seemed to run fine, i checked the codes and got:
55 Normal Operation

Took it for a drive, checked the codes again and got:
12 Mass airflow sensor/circut