Hi all. 96 Dd51t, f6a. Rebuilt head and carb. Cold idle screw (#5) all the way out. Runs good for a bit then WOT. Applying vac (with mitt vac) it high idle diaphragm has no effect in lowering rpm. Diaphragm holds vac for a bit and then very slowly loses it. Any ideas on what is causing this and how is that diaphragm supposed to work? I suspect a vac leak (intake maybe) but can’t check cause of high revs. At just cranking, vac to diaphragm is a bouncing 5-10 ish.
