Problem:
From -18 to 0 psi, fuel pressure rises to about 46psi. At 1psi the fuel pressure drops down to where it normally is at idle (about 38psi). As boost comes on, fuel pressure rises at what appears to be .5psi for every 1psi of boost (not 1:1 ratio).
What I've done so far:
-Replaced vaccum hoses
-Replaced FPR
-Bypassed FPR Solenoid
-Replaced Hotwired Supra FP with Walbro FP (later reinstalled Supra)
-Re-did the Hotwire
-Swapped TruBoost controller for Halman PRO (MBC)
-Pressure tested (slight leak at throttle body butterfly - spring area)
I don't know what else to do or check, so I'm hoping for ideas on what might be causing this.
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