I am having a problem with my S-afc II. I have an S4 with a s5 to4 hybrid, ported Wg, custom 3" intake, 2.5 dp/mp, N1 catback. 720 seconds, Walbro 255, (rewired)
Before I had the S-afc tuned to my stock turbo with no problem. But, now the only thing I did was change out the stock turbo for the one listed above. I hae 10 dyno runs with the correction going from 0% to 30%, and nothing changes. The lines are exactly the same on all 10 runs. (overlapping)

I checked the install and all is good. I called Apexi and they said that all sounds to be working right, might be somthing else. The car is running lean right now and I cant get any more fuel no matter what.

On the street if I load up the "low" with up to 15% the car boggs and hesitates. (running way rich) So its working but its not? Can anyone help? Could it be the pump not flowing enough? Fried ECU? Fried S-afc? (all works on the safc though) Thanx!

 

When was the last time you had your injectors cleaned ?
If I were you I would just sell the S-AFC, and get a Microtech or something else more reliable, and a little more versatile as far as tuning is concerned. But I suggest you take out the S-AFC, if yo uthink it could be that, and send it to APEXI so they can test it for you to see if it's working properly. Also I would post your problem up in the Second Gen Main page maybe someone can help you out there as well.