stuttering while accelerating

So, my 92 aw4 is having difficulties accelerating. Engine runs like a champ when parked, but out on the road it fails to accelerate smoothly and feels like it is bogs down repeatedly while accelerating. Happens at any rpm but is really bad when trying to go up a hill. Noticed it about a month ago after a wheeling trip and a long drive home. While wheeling I did put some small dents in the muffler and cat, but nothing too bad...I think. Since then I have tuned up the rig and done some maintenance including plugs, wires, cap, rotor. Also replaced the burned out cat and replaced the TPS. Fuel pump and filter were changed a year ago and fuel pressure at the rail is ~32. Vehicle is not giving any trouble codes either. Disconnected the battery and let it sit for the night, started it up and ran the same. Disconnected the O2 sensor and drove around, no change. I am really at a loss on this one.

Unplug the TCU and drive it shifting manually.

When it starts to occur pull off and turn the ignition to on then off 3 times before starting, see if it temporarily solves the problem. If it does, its the fuel pump most likely.

Sorry...but what is the TCU? I will have to try the pulling over and turning the key three times and starting it thing. I know I haven't completely ruled out the fuel pump, but it does seem to give me good pressure at the rail.

TCU = transmission control unit.

Under dash, passenger side.

Controls all electrical functions of the AW4.

So, I think I have tracked it down to a fuel issue. Fuel pressure at the rail is ~31 with the vacuum line at the regulator attached and ~40 when disconnected. However, when it started to accelerate like crap, I pulled over and did the same test and it was ~31 with the vacuum connected or not. No spike in pressure with the regulator detached. So, is this a regulator problem or a pump problem? I followed the Hayes manual and it seems somewhat unclear as to what is the culprit.