How 'bout... maybe?

1) A/C and lights off
2) warm engine until idle is stabilized
3) stop engine (ignition switch "OFF")
4) check for cable kinks (I assume there are none)
5) check inner cable for correct slack = .04-.08" (I assume there is some from what you said)
6) if there's too much or not enough slack, adjust as follows:

a) turn ignition switch to "ON" position (without starting the engine) and leave it in that condition for approximately 15 seconds
b) loosen the adjusting bolts on the air intake plenum and then secure the outer cable so that the free play of the inner cable will be the standard .04-.08" value.

FSM NOTE:
If there is excessive play of the accelerator cable, the vehicle speed drop ("undershoot") when climbing a slope will be large.
If there is no play (excessive tension) of the accelerator cable, the idling speed will increase.

7) after adjusting, confirm that the throttle valve fully opens and closes by operating the accelerator pedal.

Frank