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  • 1965 - 1973 Classic Mustangs -General/Talk-
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Help with Electrical Gremlin

  • Thread starter Thread starter Steve69
  • Start date Start date Apr 19, 2006
S

Steve69

Member
May 11, 2005
233
0
16
Apr 19, 2006
#1
  • Apr 19, 2006
  • #1
Hey Guys

Ive took my mustang out a few times this year and noticed a electrical problem and Im looking for some areas I should be checking. Last year
I installed a new Holley Avenger Carb 570 and a Mallory Hyfire box and
a Msd Blaster. Im also running a Unilite distributor. I also made sure I
had 12volts of powere at run position going to the Hyfire box.

The problem Im having sometimes at idle the engine is shutting off like the
switch is being turned off. Go to restart and it fires right off again. Sometimes when Im cranking the engine over it wont fire until I bring back to the run position. It hasn't shut off when driving the car which is good thing. Any Sugestions on this. I was leaning towards ignition switch.

Thanks
 

stangonline

Member
Feb 22, 2003
318
0
16
Apr 19, 2006
#2
  • Apr 19, 2006
  • #2
Hmm. Most ignition boxes have 2 wires - one that dges directly to the battery (must go to battery +, cant splice into another 12v) and one that goes to a KOEO 12v, which simply tells the box to turn on. If by chance you put both of these together and to a KOEO or KOER, you could have that problem.
 
S

Steve69

Member
May 11, 2005
233
0
16
Apr 19, 2006
#3
  • Apr 19, 2006
  • #3
Yea your right. There was a fulltime power that connects to battery
and the other wire which is ingnition power on. I did double check the
wires and there wire correctly.
 
S

Steve69

Member
May 11, 2005
233
0
16
Apr 19, 2006
#4
  • Apr 19, 2006
  • #4
What is Koeo and Koer?
 

stangonline

Member
Feb 22, 2003
318
0
16
Apr 19, 2006
#5
  • Apr 19, 2006
  • #5
Steve69 said:
Yea your right. There was a fulltime power that connects to battery
and the other wire which is ingnition power on. I did double check the
wires and there wire correctly.
Click to expand...

Ok, well the other thing to check is the amp draw. If its too high, the voltage could be dropping too low to power the ignition box. Also, just for testing, move the wire that is ignition power on directly the the battery, just to see if it fixes the problem - do not drive, or leave it like that.
 

stangonline

Member
Feb 22, 2003
318
0
16
Apr 19, 2006
#6
  • Apr 19, 2006
  • #6
Been a long time, so I might have them screwed up - I intended them to mean key on engine off, and key on engine running.
 
S

Steve69

Member
May 11, 2005
233
0
16
Apr 19, 2006
#7
  • Apr 19, 2006
  • #7
I also just added a 130amp 3G alternator and didn't think of the amps.
I have between 13 and 14 volts when engine is running. Not sure about
the amps.
 
B

bnickel

Founding Member
Aug 21, 2002
5,640
3
77
lubbock, texas
Apr 19, 2006
#8
  • Apr 19, 2006
  • #8
you may not have enough voltage to the coil. i had this problem when i had an external resistor on the car in conjunction with the factory resistor wire.
 
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