My car has this really suspicious habit. It likes to lean out(despite having raised the VAFC to the positive side of the fuel curve and using 345cc injectors) and then throw a MAP code and further lean out. Now, if i was running lots of boost, that would make more sense. But im just running 5psi. I have a missing link, but its not being used unless i want to run higher boost, sinse i can't solve this problem, i dont use it. I basically boost, throw a code, and then lean out hard. We've tried different map sensors, different ECU, adjusting the setting on the VAFC. Any ideas?

 

Your injectors are too small.

 

That might be true, but another set up i know of that runs very well was using 370cc and running to rich. If you consider that most people lower their VAFC fuel settings to levels lower than -20 as is shown in the VAFC settings thread. These people run 450cc(or so it seems to be a popular set up) so if im running in the positive range using injectors that are 100cc smaller roughly, it should easily compensate.