Hi,
Setup is a TIII with a 255 Walbro, stock fuel pressure regulator, +40s, also have methanol injection.
Problem is that occasionally and randomly the car will go from happy ~14.7 cruising and jump to ~10.5, stumble for a fraction of a second, then ok for 30 seconds, then does it again. Has no pattern that I've been able to determine, i.e. after acceleration, cold, warm, etc.
Now I was thinking that maybe it was the pump w/o an adjustable regulator, but don't want to just throw parts at it since its so random. I would think if there were too high a pressure, it would always be rich. Full boost is at a happy 10.5-11 tops. I also though maybe it was one of the methanol injectors leaking, but it seems to do it with the system off too.
Any thoughts or ideas?