[DMCForum] Re: More ignition analysis (ON TOPIC) WALT

["Walter Coe" <Whalt@xxxxxxx>]

Yeah, I checked my advance.  I used a fancy Snap-On timing
light where I could dial in how much advance to look for.
With the vacuum disconnected, I checked the centrifugal
advance.  That was fine.  Then I hooked up a hand vacuum
pump and checked the vacuum advance through the ranges.  All
that checked out just fine.  And it was a good education.  I
felt like I was doing one of my college physics labs.

I just assumed it was low system voltage since the problem
goes away if I don't let it idle for very long.  I have
tried a different ignition ECU and idle speed ECU with no
change.  I was wondering if maybe a bob-weight in the
distributor was hanging up at low RPMs.  But the symptoms
were too consistent for something intermittently sticking.
Another idea I had was maybe the idle speed switch was
sticking.  But disconnecting that didn't stop the problem.

If allowed to idle for more than, say, 15 seconds (with
radiator fans on) and then try to accelerate from a stop,
the car has no power initially and then suddenly comes to
life once it's over 1500 RPMs.  If it were really low system
voltage then I think this acceleration lag would be a more
commonly known problem.

It is interesting you suggest component temperatures.  My
car has a warm-start / warm-run problem.  When cold it
starts & runs great -- almost too much pep for a DeLorean.
When hot it also starts & runs great but not quite as well
as cold.  But leave the car sit for 40 minutes or more and
it is a pain to start.  Then it runs like crap for a minute.
I was guessing that maybe the cold start valve was spraying
too much at the wrong time flooding it, but I haven't
checked any of it.  Hell, for all I know, the engine may be
cool enough to need a shot from the cold start valve, and
it's not getting it for whatever reason.

Due to the warm start issue, I was suspecting the warm-up
regulator.  I've replaced that.  I've replaced the fuel
distributor, injectors, filter, accumulator, pump, plugs,
wires, cap, rotor, coil.  I have cleaned grounds and various
plugs/sockets.  Some of these have made a noticeable
improvement, but I still get that acceleration lag.  I'm
ready for a different kind of engine.

Martin, are you and Darren ever going to get that engine
ready for me?  If I am going to mess with the ignition
distributor then I'll want to try out that Volvo dizzy I got
from you.  What particulars are there about using it besides
checking that the bob-weights are free?  Where do I set the
timing?

For now my car has been parked for the last 3 weeks because
of the alternator.  Next I need to get rid of my McGyver
block of wood holding the a/c pulleys to the engine.  That
is still on there.  I have to remove the rear fascia to get
out the broken pulley bolt.

> Remember, Mike was using the alternator that's in your car
without
> these symptoms. In a way, I still think you're right.

What kind of battery are you using?  I've got a red top
Optima.  I figure there is none better except maybe
something deep cycle.  The Optima recovers quickly from
sitting at a light, but then maybe it discharges too quickly
too.  I might throw an antique-technology flooded-cell
battery in there and see if it acts any different.

> My plan today, is to get the engine good and hot, then
measure the
resistance of the pulse coil.

Good idea.  I'll check mine too (when I get the car running
again).  I just got an idea... maybe spray the dizzy down
with a can of freon to see if the warm start/run issue goes
away.

Walt

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