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Discussion Starter #1
I decided to replace the troublesome AAV with a manual version. Using info provided in the Spider section I bought a manually operated valve. Advance Auto Parts item # 74627.

I made a bracket to attach it to the mounting holes where the original AAV was located. I then used a choke cable attached to the fast idle lever in our '81 GTV6 (I believe this was a hold-over from the Alfetta models and not present on later GTV6's.)

Now with the manual AAV 'open' on cold starts (OK not very cold here in NC today - say 75F) the idle speed is ~ 1500 rpm. Closing the AAV drops the idle back to 850-900 rpm.

I suppose the obvious question is 'why not just use the fast idle lever to increase the idle speed?' My answer is that it was never very useful. The idle speed was not easy to regulate using it - it yanked on an arm attached to the throttle pedal mechanism. Sometimes it'd rev way too high & sometimes it wouldn't release the idle speed back to normal. And I wanted to get rid of the 'automatic' AAV anyway.
 

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Nice job. The fast idle lever actually advances the throttle, thus moving the throttle positions switch. This valve doesn't, hence it's better for cold starts.

Greg
 

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Does the '81 have the three position throttle switch? Or just a simple 'WFO' position switch?

Anyway, it does seem to start/idle better with the manual AAV. I suspect that the old automatic AAV is lazy and perhaps doesn't open enough when cold or close totally when warm.
 

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I think the switch on the 81' cuts out the O2 sensor at both idle and full throttle. If I remember correctly it's a two position switch that gets triggered by a cam type mechanism at idle and full throttle. I am away from home right now, so I can't double check.

In any case, the manual AAV works better than even a perfect factory part, especially at sub freezing temperatures.

Greg
 

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I can attest to the manual AAV working at sub zero temps,,,,
Greg, I use that and the push button cold start injector you installed on the Blue Meanie to start at ANY temp. With a little personal involvement, like a great sports car deserves, you can manually bring a great engine to temp.
I come from the old , "Manual choke" and gas pedal dance school.
 

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Exactly, plus it eliminates two expensive, and often troublesome parts from the equation, the Bosch AAV and Thermotime switch.

Greg
 

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What are the specs on the pushbutton CSI? Where can I get one?
 
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