- Joined
- Jan 1, 2012
- Messages
- 8,369
- Reaction score
- 1,214
- Location
- Eugene, OR
- My Car
- 1971 Mustang Sportroof M code
When you can't adjust the idle mixture you either have plugged passages in your carburetor or you have to have the idle speed screw turned in too far, so the throttle blades are into the transition area and not in the idle area, or both. Try getting the idle set as low as you can and then adjust the idle mixture screws, starting at about 1-1/2 turns out. What's the best vacuum reading you can get? Does the idle speed increase when you advance the timing? If so, get the idle speed up some before you try adjusting the mixture screws and idle speed. I would also disconnect the vacuum advance until you get it running right.