So i've been having issues only when starting when the car is completely cold (aka overnight). Car would crank for while before starting. Sometimes it would start in limp mode. However, After shutting down, and restarting right after, car starts up perfectly. CEL disappears as well. The only code remains is a 27CE fuel pressure code.
This all occurred after swapping out throttle actuator bank 2.
So far i've replaced the battery, fuel pressure sensor, EKP Module, Pre-cat O2's.
I've been logging the fuel pressure and i'm getting abnormally high readings. When i unlock the car which enables the pump to prime, i'm reading 675KPA - 6.75 BAR. When the car is idling - 4 BAR. When driving, it sometimes reaches 7.25 BAR (Will verify again). Fuel pressure seems to drop 1 BAR after 15 - 20 Min of sitting after initial pump prime (580KPA)
TIS is showing 3 Bar as spec for idle and 5.55 - 6.85 bar while running.
I'm thinking my fuel pressure regulator in driver side tank is bad. Any thoughts?