This problem has just about taken me down..I have a 90 horsepower engine and the problem is the motor starts fine, I cannot hear or feel a miss and it idles just fine, when coming out from the dock after idling app. a half mile in a no wake zone, I go to w.o.t and the boat wont get on plane { it takes at least 200 yards} and I can tell I am not getting the 90 horsepower that should be there but here is the kicker, I can shut down engine for 5 minutes after traveling up the lake a short distance and I believe that I could pull 4 skiers out of the water and on plane in 3 seconds, and it will run 45 mph the rest of the day and scary coming out of the hole till the next time I come to the lake...I have had the carbs dipped and cleaned, new spark plugs, new hoses and gas tank cleaned,and new filters...if I dont find the problem the first 10 minutes that I am at the lake then I will not have the opportunity until the next week because it runs like a racehorse...I thank you