On the 1985 Mustang GT, the distributor is hooked up as such so that the engine receives full manifold vacuum when the engine is cold, and ported vacuum when the engine is fully warmed up. This makes the idle higher when the engine is cold and lower when the engine is warm.
When all of this is working correctly, will the two different idles (cold idle and warm idle) from the ported and full manifold vacuum sources actually move the throttle arm position on the carburetor?
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