[V8] Power loss/stall uphill

[Steve Buchholz]

Got a weird one I need to start working on today ... thought I'd post for BTDT.  

The car runs roughly on the flat, and shutters and dies when pointed uphill.  Due to an IC problem I'm working on the fuel gauge isn't working, but it only took a few gallons of fuel when I got to walk home in the rain, thinking I had run out.  After the fill up it ran, but now it is starting to act up again.  

The fuel pump was replaced a couple years back.  I'm going to replace the fuel filter ... and check fuel pressure at the rail.  As I'm writing this I realize that the press reg might be another suspect.

LMK any thoughts you might have!  Thanks!

Steve Buchholz (mobile)