Request for Diagnostic help (sorta NC)

[Brent]

I'm begging for some help.  Please excuse the offtopic post.  If you
respond, please do so offlist.

I'm working on a friends '86 Camaro, LG4, auto, CCC carb, stock.

Around thanksgiving the car severely lost power.  The next day it would not
start.  Would crank and sounded like it was trying to run.

A tech was called, he installed a new ign module.  The car still wouldn't
start.
2nd party installed a new timing chain.  The old timing chain was fine.
Still no start.

I pulled some plugs.  They were fouled badly.  I checked the coil with DVOM.
Coil tested bad.
Installed plugs and coil.  Car lit right up. First try.
Ran great.  Adjusted timing to factory spec (off 6d).  Continues to run
good.
I notice the choke heater not operating properly (owner is planning to fix
it later).

One week later, car severly looses power,  the same as before.  Engine
shaking the car.   Refuses to start next day.
Owner cranks the car in several attemps to start the car.  No good.

I pull plug # one.  Slightly black (suspected choke heater failing), not
wet.   I crank the car and finally after pumping the throttle many times, it
starts.   It runs horribly and requires 1/4 throttle to maintain 1100rpms.
We hold the choke open and the engine gains 100 rpms. Still VERY rough.
Sounds like 3-4 cyls at the most firing.  Engine never cleans up.

I suspect ignition trouble.  So I follow Helms procedure to check the HEI.
Coil, module, pickup all test ok.  Parts  store tests module as ok.  Scan
tool reveals all sensors within spec.  M/C solenoid clicking happily.  With
the 4 wire est connector disconnected it won't start.  Dissy shaft cannot be
turned, pin not sheared.

Hair pulling out begins.

If anyone can offer a suggestion, I would greatly appreciate it.
Some other parties want to throw parts at it  (carb, dissy)  and I just
can't see doing that.

Regards,
Brent



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