[V8] Idle speed too high

[Ed Kellock]

Patient is my 91 5spd.  Idle speed is consistently a little too high, like
1100.  Here's what I've done....

-removed/cleaned ISV
-adjusted TPS
-opened up and cleaned throttle butterflies directly
-lubricated throttle rod/pivot assembly (it was and is smooth and returns
to stop solidly)
-went through everything again checking for vacuum leaks
-checked cruise control for adjustment etc., no interference

Initially I could lower it some by pushing down on the small lever at the
front and I found that I had the TPS adjusted so that it was causing the
throttle to hang open a bit.  I loosed the TPS, pushed down on the level,
backed the TPS off a little tiny bit more and snugged it down.  I
confirmed it still returns to closed throttle position (click).

The last thing I did was unplug the ISV and start the engine.  The idle
seemed right for a moment but then slowly climbed up to 1100.  It seems
like it's ECU or something.

When I turn the engine off, there's a clack in the passenger side fender
well.  I know there's some emmissions shite in there, a reservoir and a
valve of some kind, but I don't know what it should/shouldn't do.  I am
fairly sure I've never heard a clack from that area ever on any of my V8s.
Maybe I just never noticed.

Thanks,
Ed