Elevation changes idle

[lubbes07]

hey guys, ive been wheelin my 85 efi lately, and at my place i have my idle set at 1200, were at about 700 feet above sea level, when i go up on the mountain, maybe about 3000 ft above sea level, it change my idle speed down to about 500 rpms and it tries to die, i rev the motor up and let off the gas and it goes back down to the 500. Is this common? or is something wrong? any help would be appriciated. Thanks

[Ryan31783]

try changing your idle, it's only supposed to be at 750 RPMs it's the big flathead screw that's on the top passengers side of the throttle body.

Ryan

[1985toyota]

When my truck gets warm the idle goes down, so i have it set at about 1100 and when she warms up it goes down to about 750-800 kinda of strange but its a thought

[lubbes07]

so the changing in idle on elevation is normal? cause when i get up on the mountain i have to change the idle so it doesnt die, when im just sitting there.