• Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

130 amp alt upgrade DIM HEADLIGHTS???

  • Thread starter Thread starter bryanrevans
  • Start date Start date Apr 26, 2005

bryanrevans

New Member
Sep 10, 2004
296
0
0
Chicopee,Mass
Apr 26, 2005
#1
  • Apr 26, 2005
  • #1
I recently did the bolt on's listed and when I turn headlights on they are weak dim.The car had a 50 amp stock alt.When the electric fan kicks on it draws on the motor.This I kinda understand...(cheap fan controller with no relay)But the headlights I dont get?????
 
D

D347643

Banned
Jan 28, 2003
1,095
0
0
portland, OR
Apr 26, 2005
#2
  • Apr 26, 2005
  • #2
did you upgrade your wiring and i assume its a 3g so i "assume" you converted your wiring to 3g also, right?
 

bryanrevans

New Member
Sep 10, 2004
296
0
0
Chicopee,Mass
Apr 26, 2005
#3
  • Apr 26, 2005
  • #3
yes 4g wire to starter solenoid but......I had no white wire on my harness!No where so I got a 3 wire plug from junkyard to replace my 2 wire plug.I connected the j.y. white wire to white wire on back of alt and other 2 wires to new plug and plugged it in.I left the old large plug with 2 10 guage wires alone hanging??????Good or bad??????
 

bryanrevans

New Member
Sep 10, 2004
296
0
0
Chicopee,Mass
Apr 26, 2005
#4
  • Apr 26, 2005
  • #4
Every instruction I found on stangnet and magazine articles were never for a 86 5.0 My entire alt. wireing harness had no white wire in it.Just 2 10g black,1 green,1 yellow thats it!!!!!!!!!!
 

bryanrevans

New Member
Sep 10, 2004
296
0
0
Chicopee,Mass
Apr 26, 2005
#5
  • Apr 26, 2005
  • #5
4 wires total.Every other fox has a different harness.Except for those with external voltage regulator.
 

91mustangnick

New Member
Apr 12, 2005
51
0
0
Alpena, MI
Apr 26, 2005
#6
  • Apr 26, 2005
  • #6
i have a 130amp 6G alt. and i didnt have to use the white wire. the white wire on my 1991 went from one part of the alt. to the other part, and the harness didnt have a place for the white wire. car runs great.

Nick
 

bryanrevans

New Member
Sep 10, 2004
296
0
0
Chicopee,Mass
Apr 26, 2005
#7
  • Apr 26, 2005
  • #7
when i put a meter on bat with engine at idle I get aprox 13.5 volts and my batt guage is reading slightly on the minus side of half
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Apr 26, 2005
#8
  • Apr 26, 2005
  • #8
how did you wire up an electric fan with no relay?

with 20 year old wiring, you could have a decent voltage drop through that stock wiring and switches, to the headlights. i installed relays on lows, highs and fogs to help with this situation (gets battery power to the lights rather than using the recursive stock wiring).
and it sounds like either you have a voltage drop in the wiring or an inaccurate gauge (dont 86's have an ammeter rather than a voltmeter?). straight up on an ammeter gauge would be around 12.6 volts.
good luck.
 

bryanrevans

New Member
Sep 10, 2004
296
0
0
Chicopee,Mass
Apr 26, 2005
#9
  • Apr 26, 2005
  • #9
I ran the power source straight from the battery.under hood light actually.for the fan.When I tried to use a switchable power source(wiper motor red wire) the fan would kick on and off every 1-2 sec, so I ran it to underhood light.fan keeps running after I park tho
 

Nutzy19

Member
Mar 30, 2005
120
0
16
Flemington NJ
Apr 26, 2005
#10
  • Apr 26, 2005
  • #10
Call P.A.PERFORMANCE and have them send you the 15.00 wiring kit for your 86....http://www.pa-performance.com/display.asp?sku=27&rP=searching,cat@Plugs+and+Wire+Kits,cR@categories
 

bryanrevans

New Member
Sep 10, 2004
296
0
0
Chicopee,Mass
Apr 26, 2005
#11
  • Apr 26, 2005
  • #11
Thats what I have on there now.but I used the jy plug and white wire on back of 3g alt
 

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
27,512
2,813
234
Dublin GA
Apr 26, 2005
#12
  • Apr 26, 2005
  • #12
The secondary power ground is between the back of the intake manifold and the driver's side firewall. It is often missing or loose. It supplies ground for the alternator, A/C compressor clutch and other electrical accessories such as the gauges. Any car that has a 3G alternator needs a 4 gauge ground wire running from the block to the chassis ground where the battery pigtail ground connects.
 

bryanrevans

New Member
Sep 10, 2004
296
0
0
Chicopee,Mass
Apr 26, 2005
#13
  • Apr 26, 2005
  • #13
A light bulb just went off!!!!!!!When I pulled motor that wire snapped.I did a quick fix.I will upgrade that to 4 guage and securly ground that.Thanks for pointing me in this direction!!!!!!!!
 
You must log in or register to reply here.

Similar threads

S
Preparation for Holley Terminator X install – Foxbody 306 (electrical fan, alternator, MSD Ignition, etc)
  • So_Flo
  • Mar 1, 2026
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 2
Replies
22
Views
2K
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Mar 4, 2026
General karthief
2
Electrical mayhem
  • 2000ElectricGreen
  • Mar 13, 2026
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
2
Views
252
1996 - 2004 SN95 Mustang -General/Talk- Mar 24, 2026
2000ElectricGreen
2
SOLD SOLD!!!! 1993 Notchback Roadracer For Sale. She's a beast!
  • Boydster
  • Apr 25, 2025
  • Fox Body Mustangs For Sale (1979-93)
Replies
0
Views
1K
Fox Body Mustangs For Sale (1979-93) Apr 25, 2025
Boydster
For Sale 94 Cobra 408w AOD Project For Sale
  • Labora
  • Oct 11, 2024
  • SN95 Mustangs For Sale (1994-04)
Replies
1
Views
1K
SN95 Mustangs For Sale (1994-04) Apr 7, 2025
Labora
Fuel Fuel Pump Rewire, New Fuel Lines, and Installation of New Fuel Pump Hanger with AN6 Connections
  • AeroCoupe
  • Mar 12, 2023
  • Fox 5.0 Mustang Tech
  • 2
Replies
33
Views
13K
Fox 5.0 Mustang Tech Apr 16, 2023
AeroCoupe
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?