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o2 system testing



This weekend I decided to do some testing on my 86 8v.  I was going to start
with timing, but the timing test said to make sure the o2 system was
functioning properly, so I started there instead.  Of course the o2 testing
section says to make sure the timing is set correctly so it's a catch-22.
But anyway I didn't think either were that far off because the seat-of-pants
meter indicates everything is pretty much ok.  I'd just like to do some
verification and fine tuning.

So my o2 system so far is failing miserably.  I got through the quick check
test in the Bentley where you warm the engine up and read the dwell meter
(I'm using a dwell), then remove the crank case ventilation hose and plug it
and the reading should drop and then hunt around 23-27 (IIRC).  My results
at idle were in the "limp home" range and with the ventilation hose plugged
around 12-18.  It never dropped and then hunted it just went straight there,
so I don't know if the 12-18 is the drop or the hunt.  I should mention my
cat is empty, but since the o2 sensor is before the cat I don't beleive this
should affect these results.

So if I read between the lines it seems like my mixture is low and perhaps I
can correct it by adjusting it using the 3mm allen in the hole near the fuel
distributor.  But I thought this was a setting you didn't want so screw with
unless you're sure of it so I wanted to solicit some second opinions.  Or
should I continue with the rest of the o2 system tests?  But I predict that
all the tests are going to yeild similarly low results.  I'm thinking what I
should do is try to adjust the mixture to get the "quick test" acting more
normal and then verify the remainder of the tests.

ALSO, has the location of the o2 system control unit changed?  My Bentley
claims it should be behind the glove box, so I went looking there because I
remembered having a leak problem so I wanted to check out the electrical
connections.  But I found nothing.  Mine seems to be in the same location my
Bentley claims the 16v CIS-E unit is, behind the rain tray on the driver
side ... it's a big black box lableled "Jetronic."

Thanks in advance,

matt.