AH thanks for asking, allow me to clarify here:

Did I ever clean the IAC? - No, but I gave the hoses a look for cracks.
How low was the tank when I filled it? - probably a quarter tank or so (it was at about 3/8th when I started this project).
Was the power loss only at idle? - No; in fact it was almost entirely during acceleration/throttling once I reset the throttle switch and set base idle.

In-tank fuel pump - Tested it before I replaced the main pump several weeks ago by jumpering the 4 and 6 fuses with the main pump's (-) terminal disconnected so that I wouldn't confuse its sound with the transfer pump's. I could hear the transfer pump working then so I wrote that off as a possibility. There is an unspecified evap leak in that system tho as I did mention before, but I don't have a fogger machine to cheaply pinpoint it. I would not be surprised if the small fuel line inside the tank is letting air through.

The O2 sensor is 3 years old and tested fine as of a year ago. I burn a lot of oil though so possibily it might have a reason to start failing (it is located on the exhaust manifold as opposed to being right above the cat).

Buddy of mine suggested that since 'fixing' the no start but losing power at throttle the throttle sensor switch might be malfunctioning and momentarily tripping into an idle mode. It tested fine for engaging with the throttle valve but the other terminal that I tested on there wouldn't give me any kind of reading (since my multimeter doesn't have a continuity function I tested for resistance between each of the terminals and the negative terminal [black wire] on the device). I can't remember what that test was for but if that part of the throttle switch is indeed not working then maybe this could be what's contributing to a power loss during throttle/engine load?


Gotta short errand to run later so we'll see if anything's changed.