Hi all.
Great thread. Gave me the info needed to perform the work myself.
My problem was a fast idle and when it hit 2000+ RPM it was obvious that I needed to do something.
I replaced the diaphragm and the idle on my BJ70 is back to 700 RPM.
Denso has the part. Just looked up
http://densoheavyduty.com/where-to-buy/state I call a service center and had the part next day.
As my TLC is quite old I was adverse to removing anything I absolutely did not have to move. I could do the job today in about 30 minutes now that I know how. No need to remove the pump nor the EDIC. Just remove the EDIC arm. It pops off.
I just removed the plastic vacuum pipe (from the diaphragm), moved the wiring out of the way, popt off the EDIC arm and then removed the screws holding the diaphragm cover on. Used a short length of wire to pull the cotter pin out once I straightened it.
Used needle nose pliers to straighten the cotter pin (tried 10 minutes from the side then used the needle nose pliers going at it from under the diaphragm cover and that took 20 seconds or less).
On reassembly decided to use an R-clip
instead of the worn cotter pin, used allen head cap screws instead of the slotted screws. I could not find a store bought R-clip of the right size so bent up some stainless steel wire from my parts bin and the whole thing went back together in about 15 minutes. Used a rag under the IP so that when I dropped something I did not have to look too far to find it. Replacing the washer on the diaphragm was the most time consuming part of the process.