[Shotimes] Stumbling at highway speeds

[Thesing, Hunter M.]

Okay, hopefully this will be my last posting for a while, as I'm sure you're
getting tired of my stupid car.  For those of you helping me or who have been
following my progress, the car is running much better now.  Overall, I am
pleased.  However, it still has a few quirks that are bugging me.

At highway speeds (60-75) it sometimes loses power when cruising (just enough
to be noticeable).  And when I give it a little gas, it stumbles.  If I keep
pushing the pedal down, it gets worse, and then at a certain point, the
stumbling stops and it starts to accelerate.  Could this be the point where it
goes into WOT?  That could explain a few things.  I'm not sure if this is
related, but I have a check engine light that comes on intermittently, but
doesn't seem to correlate to this problem.  I'll have codes (hopefully)
tomorrow when I buy a new battery for my reader.

Any ideas?  I had an '84 Buick Skylark that had similar problems that were
corrected with a new MAF.  Does that sound like this could be it? (note:
recently cleaned MAF)

Also, possibly unrelated, my car has been stalling intermittently, only when
coming to a stop (no engine load), and not all the time.  Again, for those
following my saga, I have a new IAC now, which has helped with the idling, so
I think it must be something else now.

Again, I greatly appreciate the feedback from all of you.  Without this vast
knowledge at work, I probably would have kept my wife's Saturn to drive, since
it has been more reliable than the SHO.  Oh, well.

Thanks again,
Hunter Thesing
'93 MTX EG
Sho Shop 190 LPH Fuel Pump
K&N Air Filter
Homemade Ram Air