1993 gmc wiring/charging help

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

93.gmc.sierra

Newbie
Joined
Jan 1, 2014
Messages
13
Reaction score
2
Hi everyone.

I have a 1993 Gmc sierra 5.7 2wd that I have swapped over to carb a few years ago, everything worked fine until I removed the dash to replace it ( mine was all sun cracked) and all the ecu, wiring and the ip and all the wiring to that as well. I had planned to buy individual gauges and install those but have not done so yet.

Everything on the truck works like normal but I have one issue, while driving the truck it will drain the battery and die. Its like the alternator is not charging and the truck is just running on the battery alone. When I check the alt. it is pushing out voltage and if I charge the battery with my charger it will fire right back up and run fine until the battery dies again.

I am wondering if I might have taken something out like the voltage gauge that is needed to complete the circuit for the charging system?

All of the ecu and wiring was already un plugged so I do not believe it was any of those wires but I'm not 100%

Any help would be greatly appreciated
 

kennythewelder

Officially Retired, B31-3 (6-G) certified welder.
Staff member
Super Moderator
Joined
Jul 14, 2014
Messages
6,496
Reaction score
9,087
Location
Louisiana
It sounds like your ALT is going bad. The easiest way to check this, is to start the truck, then take the + bat connection off. If the truck keep running with the cable removed, the ALT is working, if the truck dies, the ALT is not working. The ALT should put out enough to run the truck with out being hooked up to the battery.
 

93.gmc.sierra

Newbie
Joined
Jan 1, 2014
Messages
13
Reaction score
2
I have already tried swapping the alternator out. Sorry I should have put it in the op, I have a Dc power 300amp alternator on it currently its maybe a few months old. I put an oem alternator on and it still does the same thing. I have also disconnected all the stereo equipment to eliminate from the problem even though it all worked fine before I took out the ip and ecu wiring

I appreciate the help, I guess I could still try to take the battery off.. I believe it will die because I have am out of tank electric fuel pump
 

kennythewelder

Officially Retired, B31-3 (6-G) certified welder.
Staff member
Super Moderator
Joined
Jul 14, 2014
Messages
6,496
Reaction score
9,087
Location
Louisiana
Have you done the big 3 or the big 4 up grade? here are a few videos.
xc_hide_links_from_guests_guests_error_hide_media
xc_hide_links_from_guests_guests_error_hide_media
xc_hide_links_from_guests_guests_error_hide_media
xc_hide_links_from_guests_guests_error_hide_media
 
Top