if you have the same problem as i did with my car i have a 88 honda accord dx with a a20a in it. it kept revving really high and i could not solve the problem but i made away around the problem. when i started my car it would rev all the way up to 2k and even higher and never drop no matter what i would do. i checked all the vaccum lines nothing.

If you take the airfilter out and the top cover over the carb. you will see a little flap called the butterfly flap. If your car is revving high and you push that butterfly wide open then tap the throttle cable and then the idle dorps down. you have the same problem as i did.

what i did... if you push the flap open and closed you will see a lever moving to the left on the outside of the carb what i did was put a zip tie around that and pulled it toward the front of the car. so the butterfly stayed wide open. I have not had a problem with the high revving anymore. put everything back together and you cant even tell.

its problably not the best solution but it beats having your gas sucked out revving so high.