I posted back in January that my 180 hours SFREMAN IO-520 was running poorly and cutting off at idle. After messing with re-setting pressures, my A&P/IA pulled the fuel pump and sent it off. It was full of trash and had to be overhauled. All the hoses were replaced at OH but the guys said the trash looked like flashing from inside the hoses that broke loose.
They also cleaned the fuel injectors and spider lines and reset pressures to spec but I had them increase WOT fuel flow to 28.5 GPH. 1.5 AMU’s, but all appears to be working as it should now.