Quote:

AT IDLE who cares if the metering rod pistons are bouncing up and down. Nothing is being drawn thru the main circuit, they can dance an Irish Jig all day long and it won't affect IDLE mixtures.

Heck, pull them out and see if you notice a change at all.

Now if we were on the cruise circuit tooling about, yeah, but Idle no.




Actually they can. He's talking about poor idle, at rpms at or above 850, which "could" be into the transition area, especially if camshaft, vacuum leak, whatever, is causing more than normal throttle plate opening, who knows at this point?

Fuel for idle and transition comes through the main jet/ well area, and disturbances such as "bounching pistons" can certainly affect the idle passage fuel flow.