Retired back to Bowties
Join Date: Sep 2004
Location: North Pole, Alaska
I'd change an O2 sensor before the regulator. The regulator is something that shouldn't cause your problems as the injectors send fuel in rates given to them by the PCM in relation to your throttle position.
O2 sensor changes have made a HUGE difference in my vehicle, so I now change them every two years or so.
1985 1 ton K-5, Detroit diesel, 36" tires (going bigger when money permits), 4-speed manual swap, Rockwell T-case, Hybrid lift, 12.5K winch.