Hey guys. I think I am having issues with my L67's fuel system and cannot find the solution. At first, the engine would start spitting at around 4k when accelerating and I would loose power. What's strange is that the severity of the issue changes every time I drive the car, but during every drive the severity is usually consistent. No misfire codes. No check engine light even, but fuel economy is noticeably low. So far, I have replaced the fuel regulator because the pressure was bouncing around, most of the vacuum lines under the hood, cleaned the MAF, and cleaned the injectors. Fuel pressure seems good (~40-50 psi) at any RPM when the car is stationary. I have a new fuel filter to install but the old one is rusted to the line fitting pretty well. Other than that, does anyone have any ideas about what the issue could be?