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odd voltage problem..help

  • Thread starter Thread starter jmd2914
  • Start date Start date May 26, 2009
J

jmd2914

Founding Member
Sep 6, 2002
937
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0
Napa, California
May 26, 2009
#1
  • May 26, 2009
  • #1
Im running a 3g alt with a taurus fan on a toggle switch. when i first start the car until it is warmed up the voltage will be almost all the way at the top of the meter and the amp light will be flickering. it seems like the only way i can keep the voltage down is by turning on the fan, even if the car isnt warm. also when the car is just idling its fine but when im actually driving thats why the voltage spikes. this started about a week ago. any ideas?

thanks

J
 
S

smithin813

New Member
May 26, 2009
1
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0
May 26, 2009
#2
  • May 26, 2009
  • #2
Have you checked the volage regulator? I had the same problem a while back with my 3g and it was that.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
May 26, 2009
#3
  • May 26, 2009
  • #3
Agreed. Be careful that you dont start blowing light bulbs, etc.

It takes 2 mins to swap a 3G reg once you have the alt off the car.
 
J

jmd2914

Founding Member
Sep 6, 2002
937
0
0
Napa, California
May 26, 2009
#4
  • May 26, 2009
  • #4
how do i check//change the voltage regulator? ive never had to do it
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
May 26, 2009
#5
  • May 26, 2009
  • #5
If you're seeing voltage over 15V for about any reason, chances are the reg is bad. A parts store can bench test the alt. The kicker is finding a decent reg, let alone locally. I'm still trying to find decent ones that are not real pricey.
 
J

jmd2914

Founding Member
Sep 6, 2002
937
0
0
Napa, California
May 26, 2009
#6
  • May 26, 2009
  • #6
is the voltage reg on a 3g internal? if so, can i still swap it out? or would i be better off just buying a new alt.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
May 26, 2009
#7
  • May 26, 2009
  • #7
jmd2914 said:
is the voltage reg on a 3g internal? if so, can i still swap it out? or would i be better off just buying a new alt.
Click to expand...

HISSIN50 said:
It takes 2 mins to swap a 3G reg once you have the alt off the car.
Click to expand...

You need torx bits, a paperclip, and a couple minutes.

Ford Fuel Injection 3G Alternator Voltage Regulator Replacement
 
J

jmd2914

Founding Member
Sep 6, 2002
937
0
0
Napa, California
May 26, 2009
#8
  • May 26, 2009
  • #8
awesome thanks for the write up, can i get a new reg at kragen//autozone? or is it more of a specialty part?
 
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