I have a 2003 Odessy with a 3.5 V6.  It hesitates slightly, and somtimes
drops power for a fraction of a second.  It's strange because it only does
it when the gas peddle is slightly depressed, when cruising at high or low
speeds.  No problems on acceleratation, no problems starting.  I get no
codes returned when I check the computer with a reader, and no engine light
is comming on.  The car has 56,000 miles on it so I tend not to think it
needs a tune up per se.  I checked a couple plugs, and the air filter, and
everythings alright there.  I was thinking that a fuel filter or fuel pump
might be acting up but before I test the fuel pump pressure I thought see
if anyone here has any ideas.  Could the ECM be acting up? I would think
that would trigger some codes.  Anyways, I'm stumped.  I have one idea, I
know on some cars if the gas cap isn't on tight, the car will act up, does
anyone know if this happens with this engine?  If it does, wouldn't I get a  
fault code?  A buddy of mine was having problems once and the code reader
came back with some kind of fuel problem code, and a quick search suggested
taking the gas cap off and putting it back on again tight.. problem fixed.

TIA

Paul.