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Help relocating battery

  • Thread starter Thread starter kbnugggz
  • Start date Start date May 26, 2009
K

kbnugggz

New Member
Feb 22, 2009
12
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0
May 26, 2009
#1
  • May 26, 2009
  • #1
To start off i have a new solenoid, battery, altenator, and a mini starter pulled from a 1/4 mile car working great. I recently relocated my battery to my trunk to clear my new alum. radiator and fans. I ran 0 gauge wire from the battery to the sloenoid and grounded teh neg. side to the body. I didn't see a need to run the ground to the block since i am running solid engine mounts. I left the solenoid on the fenderwell and all of the underhood wiring as is.
The problem now is the my car often decides it doesn't want to start. Some times i get in the car and it fires right up, it doesn't seem to matter if the car is warm or cold. When it doesn't want to start it just clicks at the solenoid, but sometimes if i try cranking it 10-20 times it fires right up.

Do i need to run an altenator wire directly to the battery??
Is it a ground issue??
I have run out of ideas on what the issue could be, an help would be great.
thank you
 
K

kbnugggz

New Member
Feb 22, 2009
12
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0
May 26, 2009
#2
  • May 26, 2009
  • #2
I might also add that the altenator wiring still meets the POS. battery wire at the solenoid, under the hood
 

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
27,512
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Dublin GA
May 26, 2009
#3
  • May 26, 2009
  • #3
Rear mounted battery ground wiring. Follow this plan and you will have zero
ground problems.


One 1 gauge or 1/0 gauge wire from battery negative post to a clean shiny spot
on the chassis near the battery. Use a 5/16” bolt and bolt it down to make the
rear ground. Use a 1 gauge or 1/0 gauge wire from the rear ground bolt to a clean
shiny spot on the block.

One 4 gauge wire from the block where you connected the battery ground wire to
the chassis ground where the battery was mounted up front. Use a 5/16” bolt
and bolt down the 4 gauge engine to chassis ground, make sure that it the metal
around the bolt is clean & shiny. This is the alternator power ground.




The computer has a dedicated power ground wire with a cylindrical quick connect
(about 2 ½”long by 1” diameter. It comes out of the wiring harness near the
ignition coil & starter solenoid (or relay). Be sure to bolt it to the chassis ground
in the same place as you bolted the alternator power ground. This is an
absolute don’t overlook it item for EFI cars

Note: The quick disconnect may have fallen victim to damage or removal by
a previous owner. However, it is still of utmost importance that the black/green
wires have a high quality ground..

The screwdriver points to the common body ground for the alternator, battery and computer.

Picture courtesy timewarped1972



Crimp or even better, solder the lugs on the all the wire. The local auto stereo
shop will have them if the auto parts store doesn't. Use some heat shrink tubing
to cover the lugs and make things look nice.

For a battery cut off switch, see Moroso : Category Display
is the switch http://www.moroso.com/catalog/images/74102_inst.pdf is the installation instructions.
Use the super duty switch and the following tech note to wire it and you will
be good to go.

Use the Moroso plan for the alternator wiring and you risk a fire. The 10
gauge wire they recommend is even less adequate that the stock Mustang
wiring.

There is a solution, but it will require about 40' of 18 gauge green wire.

Wire the battery to the two 1/2" posts as shown in the diagram.

The alternator requires a different approach. On the small alternator plug
there is a green wire. It is the sense lead that turns the regulator on when
the ignition switch is in the run position. Cut the green wire and solder the
40' of green wire between the two pieces. Use some heat shrink to cover the
splices. See Ford Fuel Injection How To Solder Like a Pro for some excellent
help on soldering & using heat shrink tubing.

Run the green wire back to the Moroso switch and cut off the excess wire.
Try to run the green wire inside the car and protect it from getting cut or
chaffed. Crimp a 18 gauge ring terminal (red is 18 gauge color code for the crimp
on terminals) on each wire. Bolt one ring terminal to each of the 3/16" studs.
Do not add the jumper between the 1/2" stud and the 3/16" stud as shown it the
Moroso diagram.

How it works:
The green wire is the ignition on sense feed to the regulator. It supplies a turn
on signal to the regulator when the ignition switch is in the Run position. Turn the
Moroso switch to off, and the sense voltage goes away, the voltage
regulator shuts off and the alternator quits making power.

The fuse & wiring in the following diagram are for a 3G alternator. The stock alternator uses a dark green fuse link wire that connects to 2 black/orange wires. Always leave them connected to the starter solenoid even if you have a 3G alternator.



See the following website for some help from Tmoss (diagram designer)
& Stang&2Birds (website host) for help on 88-95 wiring
Mustang FAQ - Engine Information Everyone should bookmark this site.

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg
 

silver1983gt5.0

New Member
Sep 7, 2003
116
0
0
sturbridge,massachussets
May 27, 2009
#4
  • May 27, 2009
  • #4
did you have your battery checked mine does the same thing almost like the battry is dead/dying only after the relocate,and mainly when its hot. was told its the battery isnt strong enough due to the extra 14 ft of cable.
 

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
27,512
2,811
234
Dublin GA
May 27, 2009
#5
  • May 27, 2009
  • #5
silver1983gt5.0 said:
did you have your battery checked mine does the same thing almost like the battry is dead/dying only after the relocate,and mainly when its hot. was told its the battery isnt strong enough due to the extra 14 ft of cable.
Click to expand...

Wire it up accoding to my diagrams and a good battery will work just like it did in the stock location. Copper wire is expensive and too many guys cheap out on the wiring.
 

silver1983gt5.0

New Member
Sep 7, 2003
116
0
0
sturbridge,massachussets
May 27, 2009
#6
  • May 27, 2009
  • #6
ill have to check and see if i got copper wire i did use 0 gauge like the above guy did but not sure what type i know it was like 120 dollars for a 20 ft roll
 
P

phutch11

Member
Nov 14, 2005
328
2
18
May 28, 2009
#7
  • May 28, 2009
  • #7
Just go to a welding shop and get some more 0 guage wire and run it from the negative post to the block.

It will solve the problem.

Good luck...

Posted via Mobile Device
 

mob

the guy who hits on his mom
20+ Year Stangneter
Oct 3, 2003
2,566
136
104
Dallas, TX
May 28, 2009
#8
  • May 28, 2009
  • #8
Dont run a wire from the battery ground to the block.

How long is your ground cable now? Ground the battery close to the battery, use a wire no longer than 3 or 4 ft long. Then run a ground wire from the engine to the chassis anywhere you can. I did it from the stock engine ground spot to the sway bar mount.
 
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