Toyota Repair: 4Runner warm starting problem, battery cables, starter relay

Question
I have a '91 4Runner (100k), that runs great but has a very quirky problem. It only happens under these circumstances: I drive for a while until the engine is warm (more than about thirty minutes or so), and then turn off the engine. If I re-start it right away, it will start no problem. But, if I let it sit for about thirty minutes or so it won't start. All the electric works (lights, radio etc), but nothing happens when I turn the key--there's no sound from the starter like it's trying to turn over, although there is occasionally three or four clicks, but not loud. Then, if I wait about 15 minutes (usually when I'm on the phone with AAA), it will start with no problem, as if nothing had happened, and will start and run consistently until the next time I try and start it under the same circumstances--a warm engine that's been sitting for 20-30 minutes. I've taken it to a handful of garages, including a Toyota dealer, and they have replaced the battery, the solenoid, the battery cables, and the starter twice. Nothing has affected the problem in any way. Any ideas? It's making me crazy...

(Also, I noticed a very similar problem you answered a while ago --http://experts.about.com/q/832/3792143.htm -- I'm totally ignorant about this, but is it something where if I went to a dealer/mechanic and said "please install another starter relay under the hood", they'd know what I was talking about?)

Thanks so much...

Answer
I'm not sure if they would know what you were talking about but it seems to be the solution to the problem since I have fixed my own 4 Runner this way and others on this website.
The solution is to install a small relay in the starter system, I have gone through the same thing, replacing starter, the relay, wiring and so on without improvement, after installing the extra relay the problem is fixed.
I have no idea what the cause for the problem is other than that there is a voltage drop somewhere that causes not enough current to reach the starter, the solution is simple and inexpensive, please provide an email address and I can send instructions and a wiring diagram how to hook everything up.