I'm away at school right now and a friend called me about a problem he's having with a p1259 code. I did some searching on here but couldn't find anything related to fuel being cut off around 5000 rpms. He said the problem started right after installing a vafc 2. I suggested he look over his wiring, but what else could be throwing the code & cause the fuel cutoff?

The car is a 2000 civic ex, h6a ecu I believe. Thanks!

 

P1259
VTEC System Malfunction