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STA Terminal...6 volts output, why?

  • Thread starter Thread starter my9302002
  • Start date Start date Oct 3, 2010

my9302002

Member
Oct 28, 2007
88
1
6
Oct 3, 2010
#1
  • Oct 3, 2010
  • #1
Just hooking up the electric choke on my Holley in the 68 302....Checked the voltage at the STA terminal on the back of the alternator with car running and am gettting only 6 volts..
Car runs great...What's going on?
Car has stock alternator, everything electrical works great.
TIA,
Drew
 

my9302002

Member
Oct 28, 2007
88
1
6
Oct 3, 2010
#2
  • Oct 3, 2010
  • #2
Anyone?
 
2

2+2GT

10 Year Member
Apr 25, 2009
3,333
10
79
Southeastern Pennsylvania
Oct 3, 2010
#3
  • Oct 3, 2010
  • #3
Is the electric choke working?
 

my9302002

Member
Oct 28, 2007
88
1
6
Oct 3, 2010
#4
  • Oct 3, 2010
  • #4
Haven't hooked it up yet.
I'm sure it will work, but at a decreased efficiency.
Just wonder why I get 6 volts when it seems that all the posts I searched show it should be 12v.
 

rbohm

Founding Member
Apr 12, 2002
6,698
550
204
tucson,az
Oct 3, 2010
#5
  • Oct 3, 2010
  • #5
its very possible that the alternator is on its way out. take it to your local parts store and have them bench test it to be sure. another possibility is that the regulator is going out.
 

my9302002

Member
Oct 28, 2007
88
1
6
Oct 3, 2010
#6
  • Oct 3, 2010
  • #6
Both are new.
Will check the battery voltage to see if I get the 13-14v
with car running and take it from there.
 

Max Power

Active Member
Jul 31, 2003
1,774
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St Paul
Oct 3, 2010
#7
  • Oct 3, 2010
  • #7
Is the STA terminal supposed to deliver 12v?

I know many factory electric choke equipped vehicle in later years were wired from the alternator, and the factory choke don't require 12, something like 6-8 if I remember correctly. I think many people have problems with this when using a holley and use the factory wiring on later model cars.
 

my9302002

Member
Oct 28, 2007
88
1
6
Oct 3, 2010
#8
  • Oct 3, 2010
  • #8
So the STA terminal only puts out 6v and my alternator isn't malfunctioning, right?.....then I need to wire in a 6v switched relay to get the full 12v to the choke.
 

Max Power

Active Member
Jul 31, 2003
1,774
1
36
St Paul
Oct 4, 2010
#9
  • Oct 4, 2010
  • #9
Or you could use another source for 12v, like most people seem to do.

Make sure to use any source that is 12v with the key on, but 0v with the key off.

The factory uses the alternator source because it only provides voltage when the car is actually running. This is to prevent the choke from heating up when the car's key is merely in the accessory position. In the real world, that is not a very big deal, as most of us don't leave the ignition key on for any length of time without the car running. If you are plying your car stereo at a picnic or car show for a long time, that would be a problem, but most people don't do that.

First thing I would do is find out of the Holley will work with the 6v. If it doesn't, I would just find another 12v source rather than mess with relays.
 
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