ok heres what i have, 91 civic hatchback with the 1.5..its got 136k miles on it and runs awsome, uses a lil oil but only when im to the floor. but my question is, it idles fine but if i rev it above idle it surges..say it was reved to 1500 and held there, it will drop to about 1300 and miss exactly 3 times, go back to 1500 and drop back to 1300 and miss 3 times, and it will keep on doin that in a rythm. What could this be? it runs perfect while the engine has a load on it. Could it be a air leak somewhere??any help would b appreciated. thanks