Can anyone tell me what is the little roundish green gizmo in the small vacuum line that basically runs from one side of the throttle body to the other, under the air intake duct? (it might be only on manually tranny cars, but I'm not sure).

In the Haynes manual, you can see it on the illustrations on p. 133 (top right and bottom left).

What does it do and is it necessary (since I broke mine while removing the vacuum hose)?

many thanks.

 

probly a check valve

 

DELAY VALVE for the double throttle diaphram. See INTAKE AIR SYSTEM in the manual that is online. Seems to be there as a damper for the input to the double throttle diaphram. So it does not jerk open, shut, open, shut. All my double throttle diaphrams are busted and I've yet to find a good one in the wrecking yard.

 

ive got a spare dashpot, thermowax, 1way delay valve, diaphragm, and throttle plate set.

if i wasnt so lazy, i could mail it to ya.

btw,for those who dont know: all those parts are removed when you do the "throttle body mod"

 

I got a one way check valve from Checkers for the delay valve. But the throttle body mod removes that whole assembly.

 

I know that if you put it on backwards your idle will stay up at about 1700rpm. Did that when I started my new engine. Couldn't figure what was wrong with it. Then I remembered that thing on the way to Walmart

James