hello.

i want to know what exactly this is also had a code p0090 Fuel Pressure Solenoid Circuit i just got a evo 8 like 3 months ago and so i found a broken solenoid believe its EGR vacuum replaced it and still did the same low RPM idle. i want to know whats a Fuel Pressure Solenoid Circuit i don't really know about evo so i am learning little by little. help me out guys. thank you