Binding Accelerator Linkage Idle Issue
 

OK, I've been a good boy and worked through the various recommendations available to solve the high idle and pulsation issues with this 84 GSL-SE. Everything is clean, TPS is adjusted, etc. I have determined that the main problem is the primary throttle valve position.

"Check that the accelerator linkage returns fully and does not bind" (pg 45, FSM). Well, mine does not return fully and it does bind! If I give a shove to the linkage and close that valve, my erratic idle disappears. I go to a steady, non-pulsating 800 RPM beautiful smooth idle. It's like, "you can read the menu but you just can't eat!" I KNOW that idle is there. I can produce it, but can't maintain it. Soon as I let off the pressure on the linkage, that valve swings up just enough to botch everything up again.

Someone, please suggest the fix! I believe it will be either a replacement of, or some form of cleaning and lubrication of the linkage. This is so close, I would hate to make a mistake now. That linkage is full of springs that look just like the ones that went flying off my TR6 last time I went to be a hero and disassemble that! :uh:

Most of the linkage is hidden behind and under the dynamic chamber. A good cleaning and lube may solve the problem, but it's easier to clean and check it off of the engine. I do not recommend making ANY changes on the linkage or stop screws if you do remove the DC/LIM. Only cleaning and lubing.

Once you have lube it, start looking for tiny vacuum leaks. Start with the TID and work back/down from there.

I have applied Mystery Oil to all the moving elements, including the springs. This was done after giving all this a good douche with Kastle Dragon Fire. The application of oil was liberal. I removed the air tube which gave access to the primary and secondaries, which were done as well with Dragon Fire, then soaked with WD-40.

There is clearly a "resistance" remaining somewhere in the linkage. Standing on the passenger side looking at the linkage, the far right side,(closest to the front) is a spot where if I press downward I can feel a stop which can be pushed past. While doing this, I can see the primary valve closing down. All my idle issues resolve when that valve closes. It almost seems like the cam roller in the fast idle may be impeding the movement, but it has been really well cleaned and very well lubricated. Some thread mentioned something about a bind in the valve itself due to carbon. I've done my homework and I am putting in the time. I just can't seem to get the results!

Any suggestions welcome.