Here's my story.
I have a 3-w 150. Had it many years with no issues at all. This Sunday had two perfect flights. Then on the third flight as soon as I do the clearing turn on takeoff and level off the engine sags to near idle. Land the plane and check it on the ground, it idles good and no problems to WOT. Take off and the same thing. Open the high speed needle. Same thing.
Can't get it to go bad on the ground.
It starts easily every time. If i pull the throttle back to idle it will die, but restarts every time. will run good on the ground, but not in the level
Where do i look? Dennis