Hello, all, I have a couple of problems with a 1991 Accord that I
can't seem to find a definite answer for. It's a 4 cylinder,
automatic with 220,000 miles.

This my girlfriend's car, so I don't drive it that much, but I've
driven it enough to see both problems.

First, the check engine light comes on from time to time. It may come
on and then go off after restarting the car. I've checked the engine
code (by jumpering the little connector under the glovebox and
counting the CEL flashes) and I get a code 1, which is supposed to be
the O2 sensor (not sure if that's the upstream or downstream sensor (I
think there are both on this car but I have not visually verified
that). This problem has been occurring for several months, even
before I did some work on the car's engine, so I don't feel it is
related to any recent work on the car.

Before I mention the second problem let me say that one month ago I:
replaced the timing belt, timing belt tensioner, spark plugs,
distributor cap, distributor rotor, spark plug wires, and the valve-
stem seals. Afterwards it ran fine, no problems evidenced at all, but
I probably should mention that work, just in case it matters.

The second probem occurred last Saturday. The car had been driven and
warmed up and then parked for about 2 hours. After starting the car
we drove it about 6 miles and the car exhibited loss of power. We
stopped at a store and killed about 30 minutes and then went back to
the car. We were going to my home about 60 miles from where we were
and I drove. The car ran fine until the last 3 miles or so. I was
driving about 80 mph when the speed started dropping and it felt like
it had lost power, yet it didn't feel like the engine had died, it
just decellerated gradually. I pressed the accelerator to no avail,
however, when I pressed the pedal all the way to the floor the car
downshifted and surged hard, full power. So, it ran fine at wide open
throttle (WOT). I lessened the pressure on the accelerator and let it
return to about where it should be for 70-80 mph and the car upshifted
and then exhibited the loss of power again. I repeated the WOT,
downshift, ease-back, upshift sequence twice more before I reached my
exit from the hiway. However, once I had slowed down for the exit,
and for the remaining 1.2 miles or so to my house, the car ran
flawlessly. It never died, I never killed/restarted it, nothing.
Just slowed down, exited the hiway, boom! ran fine.

Any ideas or suggestions on what is going on with these two problems?
Is it worthwhile to replace the O2 sensor, or should I remove it,
inspect it, check the connections, etc. and try to finesse this
thing? Anything relate that to this newer problem of power loss?

Thank you for your help.

--HC