Good luck.
I remember a dude built an engine (RB30DE, he is builder so was doing it for fun), filled up at a dodgy fuel station, engine seized on the driveway out of the place. Didn't get a cent.
Water in fuel or something.
I never fill up at Caltex or BP, always with Mobil (Now 7 Eleven). Helps when they're closest to my house.
Change your fuel filter, maybe get injectors clean if they're old.