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2g alternator issues during idle.

  • Thread starter Thread starter 18hhuerta
  • Start date Start date Aug 7, 2021
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    5.0 alternator alternator issues charging issues foxbody
1

18hhuerta

New Member
Aug 7, 2021
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Salt lake city
Aug 7, 2021
#1
  • Aug 7, 2021
  • #1
Just recently replaced my 1989 lx 5.0 alternator with a new 75 Amp 2g alternator. Had to crimp in the white wire and two black with range striped wires to the vehicles harness. I've noticed while idling the battery stays around 12v. When accelerating the voltage goes up as if the alternator kicks in. Does it matter which black and orange wire I crimped together to the vehicle harness. They both look identical. Car starts perfectly fine every time just don't want battery to die one day in the middle of a cruise.
 

Dan02gt

mazing how much gas smell came from that tiny hole
20+ Year Stangneter
Mar 2, 2003
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Greenville, NC
Aug 10, 2021
#2
  • Aug 10, 2021
  • #2
Can I assume you replaced the alternator connector when you replaced the alternator? The black with the orange striped wires both go the the same place at the starter solenoid on the firewall so it shouldn’t matter which one you used. You might have gotten a defective alternator. If that’s the case strongly consider upgrading to the 3G alternator. It’s a easy upgrade and much better than the old 2G.
 
1

18hhuerta

New Member
Aug 7, 2021
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0
1
Salt lake city
Aug 13, 2021
#3
  • Aug 13, 2021
  • #3
That was my guess! Got a new alternator ordered thanks for the reassurance!
 

Boostedpimp

20+ Year Stangneter
May 8, 2003
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NJ
Aug 13, 2021
#4
  • Aug 13, 2021
  • #4
Also make sure you have the stock size alternator pulley or smaller or you won't get as much charge volts at idle
 
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