On Wednesday, August 5, 2015 at 4:11:55 AM UTC-5, John G wrote:
Uncle Monster brought next idea :
On Wednesday, August 5, 2015 at 2:48:16 AM UTC-5, micky wrote:
In alt.home.repair, on Wed, 5 Aug 2015 00:08:59 -0700 (PDT), Uncle
Monster wrote:

On Tuesday, August 4, 2015 at 11:19:17 PM UTC-5, micky wrote:
In alt.home.repair, on Tue, 4 Aug 2015 16:38:18 -0700, "Snuffy \"Hub
Cap\" McKinney" wrote:

This just started.... or at least I just noticed it. With the
headlights on dim and engine warmed up and idling, the brightness cycles
from normal to slightly dim. Cycle time is around a second. When I rev
the engine slightly, they return to normal steady brightness.

When running with or without lights, the ammeter is just right of center,
slightly charging, in the normal position.

I don't suspect a connection -- within the last 2 months, I removed and
cleaned all the battery connections, including regulator and other parts
when I was fixing a grounding issue.

Battery cranks start just fine. No other indications of failing battery.

Thanks folks,

Snuffy

Do you have a tachometer? Does the RPM oscillate?



I was wondering the same thing because many vehicles have an tiny idle
speed motor which moves the throttle as needed like when the AC is switched
on and the idle speed increases. I'd pull the air cleaner so I could see
the throttle body to see if the throttle is being moved by the idle speed
control motor. The engine control computer could be affected by a dirty
mass air flow sensor which could cause the idle speed fluctuation. (¬?¬)

I dont' think that had mass airflow sensors or ECCs when they had
regulators, but otherwise, a good idea.

Well heck, the OP did't mention the year and model of his vehicle. I just
assumed it was built in this century. ¯\_(ツ)_/¯

[8~{} Uncle Assuming Monster

It seems to have an Ampmeter and are you old enough to remember when
cars had them? :-Z

--
John G Sydney.

My fuel injected SUV has an ammeter in the dashboard. ͡° ͜ʖ ͡°

[8~{} Uncle Amp Monster