More on '747 IAC & idle

[rr]

I figured out why the idle will not come down as the throttle
blade screw is turned in: The throttle follower kicks in. Yep,
if there is any throttle follower added steps, the idle logic is not
in effect.

The throttle follower tps% bias point is typically set at 1.5% to
2.3% tps. This is the value at: 0x5EF. I've seen as much as 5%
tps when cranking in the throttle blade screw. The reason an ecm
reset corrects it, is that a new 0 tps% setting is read at powerup.

So it seems that setting (temporarily!!!) the TF start bias to say,
20% tps, you can play with the throttle blade screw to get the
IAC count desired. Then set the TF tps% bias back to normal.

BobR.



----------------------------------------------------------------------------
To unsubscribe from gmecm, send "unsubscribe gmecm" (without the quotes)
in the body of a message (not the subject) to majordomo at lists.diy-efi.org