Possibly OT, ??s about a GM feedback Q-jet

[ae2598 at wayne.edu]

I'm kinda at a loss to figure out exactly what I have here, so I'm turning
to you guys for advice.  The vehicle is an '85 K5-Blazer, with a
computer-controlled (somewhat) Q-jet.  I got it for cheap because the gas
stations that worked on this thing in the past apparently couldn't figure
out what to do with it (other than replace everything underhood!) and it
still runs lousy.

The first thing that I find odd is the HEI distributor.  It has advance
weights and a vacuum can.. In fact, the only way in which it differs from
the "standard" HEI is the use of a 5-pin module, and an extra harness
hanging out the back.  The pickup coil apparently feeds a signal to the
ECM as well as the module.. probably a timing reference signal.  This
harness has been butchered by previous repair attempts, and probably isn't
giving much data to the ECM anyway.

The next thing that's not exactly right (IMHO) is the carb itself.  It has
a M/C solenoid, but no TPS or IAC.  Every description I read about the C3
Q-jets shows at least the M/C and TPS, and usually an idle air control,
too.

The ECM seems a bit un-sophisticated.. It is in a very small package, and
has a single connector with only 7 wires connected!  No ALDL that I could
find, and no provisions for a PROM.  The service number is 16042121.

Anyway, what I would like to do is make this a non-computerized motor.
The distributor seems easy enough, I'll just plug in a 4-terminal module
and all it a day.  As far as the carb, what will be the result of not
connecting the M/C solenoid?  Are these carbs capable of metering fuel
without the help of the ECM, or should I just find another Q-jet?

Anyone with ideas to share on this would be appreciated..  the carb seems
to be dumping way too much fuel into the motor at this point, and I'd like
to solve this as cheaply as possible!


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