So I have a 1982 22r completely rebuilt including the carburetor, Truck has been de-smogged and vacuum lines are hooked up like Canadian 1983 4x4 diagram.
I have something causing the engine to idle around 1200 rpms I originally set it for about 800rpms. It will intermittently drop back down to 800 RPM on occasion. When it does idle at the 1200rpm range… I cannot adjust the idle down via the idle screw, it will keep idling at 1200.
I notice that when I hit a good size bump on the road it will go back down to normal idle range setting 800rpm.

 

I got a can of starting fluid last night and sprayed around the manifold in hopes of finding a vacuum leak. I did not get any idle surging.

 

High/cold idle still intact and working right?

 

Guess Ill have to research that item and take a look.

 

That kind of sounds like something is getting stuck or hung up and then getting knocked loose on a bump. Might try to WD-40 all your carb linkage on the outside.

 

Thanks 83 Toyota.
Ill try that. I was thinking linkage issue as well but I couldn't find anything last night. a good spray job might loosen it up.

 

Just curious, if your motor is desmogged then why do you have the vacuum lines ran like a Canadian model? The only vacuum lines you should have would be for the distributor advance and brake booster.

 

So it's the fast idle cam not disengaging....
Any way to adjust it to disengage?
The cam on my linkage does not look like the one in the Haynes manual, asin carb

 

Put a picture up

 

 

So if I tap on the linkage with my finger it will dis engage the Fast Idle, when I apply throttle the fast idle cam will re engage.

 

Is this thing moveing back whennit reengages

 

Im going to double check the Vacuum diaphragm tonight.

I notice the area in my red circle looks off??? I believe this was at the disengaged position.

 

Here is a couple shots of mine

 

nothing really jumps out as being off. But that peice works off gravity so if bumps affect when it engages and when it disengages that peice and the one on the throttle it catches are worth looking at

 

Ill lube those areas. It was working fine and now it has this issue.
I sprayed it down with some lubrication but maybe its binding. Ill see if they need a little bending and tweaking.

 

Might be the arm on the back of the diaphragm sticking inside the vac diaphragm I noticed there's a pretty good rub mark on this spare carb I got right where the arm and diaphragm come together probably wouldn't hurt to put some lube there two

 

Yea I seen that and Im planning on getting that area.

Thanks for the pictures! Its hard to tell when its on the truck.

 

I've been having this same problem for a while and have narrowed it down to the same areas....

About to undergo a frame swap so I am going to do some motor attention while I can get at it 360 degrees easily after the cab comes off.....

Let us know if you figure it out if like to know what it is

 

Its the BVSV, its not kicking on the vacuum to retract the choke diaphragm. I by passed it and applied manual vacuum (mouth) and it actuated properly. I checked the vacuum at the BVSV and it was no good. (1982 and down is a TVS instead of BVSV)

Now I need to hunt one down or by pass it some how. Dang I hate Electric choke carburators