I saw a guy at the track making adjustments to the fuel pressure regulator claiming it made the car run better due to richer/leaner mixture. So my question is, how does the fuel mixture relate to the fuel pressure regulator? I thought the fuel mixture (or fuel map) was preset by the ECU, correct?
George '89 DX-Hybrid-D16Z6, 127k miles "Seats, Suspension, Engine, MSD, next=heat reduction!"
