I've already checked the vacuum advance line. I sucked on the hose going to the distributor and the advance works and holds. No leaks. Did the same to the choke unloader dash pot and it moves and holds. No leaks. Now that the engine runs smooth at idle should show no vac leaks. There are five functions to a carburetor. Idle, above idle to max throttle, power, accelerator pump and choke. Something is screwey when an engine idles but needs 90% choke to run above idle.