Honda Pilot "Fluttering" throttle

I have a 04 Pilot w/130k miles. Having a “fluttering” problem once I reach crusing speed. If I let off the throttle then “toe” the pedel again, I get this wooshing sound as if I loose compression for a second. The RPM’s will jump about 500 rpm, then settle down to normal. I had the EGR valve replaced when I heard there was a silent recall on these but that did not work. My mechanic cannot figure it out. (By the way,I know this is not a transmission problem. Any suggestions out there?