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720 Carb Let's talk Fast Idle Relay ?

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I've read a few post here and there. I'm trying to resolve a fast idle issue. 1984 720 2.4L standard trans... cranks up...idles high appears to want to drop a few...then up then back down...never under 2K or more...I have not yet taken it out on the road. Not tagged yet., Still getting it in road condition. Idle issue could be anything... Thanks for any suggestions or advice. 

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There is no fast idle relay as such but there is an idle up solenoid if you have air conditioning.
There is a fast idle cam set by the choke and it should release when the choke warms up and opens. Warm up the engine take the top off the air filter and look. If the choke is still on this is most likely the problem.
If the choke is fully open then possible the fast idle cam is stuck. This is the fast idle cam . It's fully on at the moment and holding the throttle part open. As the choke warms and releases the cam drop down in steps till normal idle is reached....

To check hold the throttle at lease partly open and open and close the choke plate. You should see a vertical linkage pull the fast idle cam up into position. When the choke is opened, the cam should drop out of the way. Spray with carb cleaner or WD-40 and work the linkage up and down the rotated the fast idle cam till it moves freely.


Other causes of a fast idle...


Throttle cable too tight holding the throttle open too much.


Idle speed screw turned in too much holding the primary barrel open.


Secondary barrel stuck or jammed open by foreign object and not closing. Look down barrel with flashlight. Try pushing closed with pencil. Check vacuum diaphragm linkage for sticking.


BCDD set too sensitive and not shutting off.



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