Fuel cut, no CEL, no codes, no boost
Helping out a friend. 2004 WRX, has performance problem. Feel like it hits fuel cut. Problem came on suddenly, worked great before with no changes. I checked the car out, found a few small boost leaks, fixed them. Intake test good, no leaks with smoke and 20psi test pressure. Car still hits fuel cut between 3500 and 4500 RPM. No codes at all though. I swapped the car to run wategate boost just for testing. at only 6-7psi of boost it still hits fuel cut. When it happens MAF numbers are up around 120 g/s, seems high for low boost levels but I'm not sure. AFRs go lean right after the event so the ECU is cutting fuel.
Anyone have an idea what it is? I can post logs.