here is a sound clip, start at about :55 or listen to whole thing!
model is tg9s060b12mp11 luxaire, which comes up as York most places.
Anyhow, what's the best way to diagnose if this is a motor problem or a capacitor or whatnot.
Here is how much I know about furnaces - I found out how to take the panels off. And there is a kill switch on the wall.
Sounds like the capacitor is dead/dying.
If you have a capacitor tester, or a multimeter with a capacitor test feature, you can test the capacitor. There should be a micro farad rating on the capacitor (e,g, 10µF), and a variance percentage. When you test the capacitor, it should be withing the variance percentage. If it's not, then it's bad. For example a capacitor rated 10µF ±6%, should test between 9.4 and 10.6 micro farad. If not, then it should be replaced.
