Rep Power: 0

hi. ive got a civic 1.5 vtece 1997 and for the last few months ive noticed a probelm with the acceleration. when i start off in first accelerating normaly then change to second and if i put my foot down it will accelerate up to about 3000rpm then it will fall down to about 2700rpm then start accelerating again. ive also noticed i get the problem when i change down, like if i was in 4th gear coing to a roundabout and changeing to 3rd then if i put my foot down the same thing will happen. it all seems to be happening around 2200 rpm and 3000rpm but sometimes if im in 3rd gear it will happen from 3000rpm onwards. it seems to accelerate ok if i do it normal. there doesnt seem to be anything else wrong with the car, doesnt burn oil etc. ive also checked the oil level and its fine. anyone got any ideas whats wrong?