timing, maybe? dirty throttle body?

------------------------------

I always try the cheapest fixes first . . I'd run two tanks of Gasohol
thru it and see if anything changes. It could be that your timing belt
has jumped one tooth, but cam timing is easy to check. If you said it
sometimes also stalls (at stop sign) during the first three minutes of
warm-up, I'd say it had tight valves.

If 1,800 - 2,000 rpm happens to be your usual highway cruising speed,
it's your Throttle Position Sensor, especially if you do long drives on
the prairies.

'Curly'

have been having an identical problem & finally managed to solve it this
weekend.

first, eliminate the usual suspects, like gummed up injectors & pcv
valves, ignition system, etc.  i did all this, and while a new pcv valve
 made a difference for me, and the injector cleaner [started spitting
filth all over the tandem valve in my dual injector civic], the problem
improved significantly, but never went completely away.  and it had been
mostly ok in summer heat, but a couple of times driving up that big hill
on the 5 out of l.a., it started to over heat.  thought it was just the
fact that i was gunning it & the weather was over 100F.

bottom line, i finally decided to test my thermostat.  well, not only
was it opening at nearly 90C, as opposed to 78C, it also wasn't opening
fully.  so, new oem thermostat [plus thermostat rubber - very important
as the original was pretty much ready to fall apart] and the car's just
perfect again.

oh, and regarding throttle position sensor, that is a potential cause,
but you'll /definitely/ get a code from the computer if that's detected.
 you won't from the thermostat.

1800-2000 RPM hesitation could possibly suggest classic EGR system
problems. In particular, some clogged EGR ports from carbon build up,
causing an overflow of EGR gases to enter other unclogged passages. To
test, disable the EGR by
removing and plugging the vacuum hose from the valve and test drive.
Note: If the CEL illuminates, then reset after testing.

Honda dealers sell the replacement port access plugs for those who are
DIYers. The dealerships probably do this service more often then you
think, since these cars have racked up alot of miles. A while back,
someone posted a link to EGR port cleaning. Try googling around for more
info or get an estimate from a reliable shop or dealer to do the service,
if this is indeed the case.

Just a thought...Good Luck

--
Mike

Cured my wife's Prelude of a very similar problem by replacing the
distributor cap and rotor arm, the old cap had dampness inside that always
came back no matter how often I cleaned it (even baked them in the oven for
2 hours @ 100 degrees C)and this made no difference.

Had the same problem many years ago with a 1976 Toyota Celica that would
start to cut out as the engine temp approached normal.  This (I eventually
found out) was caused by having water down the sparkplug wells (not much
either about a teaspoon full or so in each) this got in when I had the
engine Steam Cleaned and was only a problem when the engine reached
sufficent temperature to turn the water into sream, which couldn't escape,
before the engine reached full temp there was no problem and as it was
winter and most days were sub zero I was having to go 8 or 9 miles before
the car reached full temp and work was only 4 miles away.

Hope this is of some use

G