Hi Folks,
    Finally did a tune up on my newly aquired 88 GL, and it's running fine.
There is this quirk though- it was running rich before, and still does,
unless I run it with the brand new o2 sensor and ISV disconnected.
    I want to use the ECU for what it was made for, but it just isn't doing
me any good right now.  Here are some diagnostic clues:
    -Thermotime/temp sender to ECU performing to Bentley specs
    -Bosch AFM new-ish to PO (within a couple thousand miles)
    -Fuel regulator recently replaced by PO
    -Starting cold with ISV connected and o2 sensor disconected, engine revs
to about 2700 rpms, and just stays there- even after everything warms up.
Starting cold with with both ISV and o2 sensor connected, it will do the
same thing, until it warms up. Then the idle drops to a shakey 700 rpm, and
I'm back to square one: a stinking superfund site on wheels that drives like
it has double pneumonia.
    -PO, a super decent fella, says the owner before him may have tried to
trick-out the engine in some way.  I'm tracking him down to find out what,
if anything, he was up to.
    -The tune-up so far isn't exactly complete: my intent was to replace all
the needed replace-ables(plugs, filters, oil, wires, cap and rotor, O2
sensor), then bring to a shop for timing and CO/idle adjustments.  This may
be completely  bass-ackward?
    -Yes, its true, I'm a newbie.

    Any ideas are welcome: further diagnostic tricks, advice, scolding, etc.

Matt
88 GL