Installed truck alternator, did the big 3 upgrade and still having voltage drops
11-01-2014, 06:59 PM
#1
Teching In
Thread Starter
Join Date: Aug 2008
Location: somewhere
Posts: 5
Likes: 0
Received 0 Likes
on
0 Posts
Installed truck alternator, did the big 3 upgrade and still having voltage drops Hello, guys. I have read all threads on the alternator fix, did what was suggested and my voltage is still dropping. I've gone through 2 truck alternators, a duracrap gold truck alternator and most recent a brand new acdelco 145 amp truck alternator. I did the big 3 upgrade, bought a new battery and I changed my fans too. Because when fans kick in and I am at idle with my foot on the brake thats when I notice the biggest drop(plus they were the original ones). I have checked every ground possible...and the voltage drops.
The only thing I haven't changed is the alternator connector. I have the single wire plug. Would this be next part to replace?
The battery is charging fine, the alternator at operating temp drops to 13.2-13.5 with all the accessories on. Sometimes while driving, the gauge shows the voltage fluctuate from the red to a little above 13...
Any help is appreciated.
1999 trans am
The only thing I haven't changed is the alternator connector. I have the single wire plug. Would this be next part to replace?
The battery is charging fine, the alternator at operating temp drops to 13.2-13.5 with all the accessories on. Sometimes while driving, the gauge shows the voltage fluctuate from the red to a little above 13...
Any help is appreciated.
1999 trans am
11-01-2014, 07:19 PM
#2
yes. if it were me that would have been the first thing that i replaced.
that one wire is the alternator turn on signal from the PCM, it has 5v on it from PCM and that's how the alternator knows it should output. if you disconnect it then the alternator doesn't charge. if that connection is at all flaky such as driving down a bumpy road or typical engine vibration and the connection loses contact the alternator output will drop in an out.
11-01-2014, 08:13 PM
#4
whatever you do, that wire and connector on the end has to make solid connection with the connector inside the alternator.
many times it's the 4-pin plug that plugs into the alternator you need to replace because it's that male/female spade terminal that doesn't grab the terminal inside the alternator tightly. google 4-pin alternator plug for GM alternator (CS130D is alt. model) they are easily mail ordered.
with your oem plug on the wire, there's sometimes no way to tell if the electrical connection is solid when it plugs into the alternator, the plastic connectors might plug in to each other well but you don't know what's happening electrically. so i would just spend $10-20 on a new alt. plug at the first sign of problems.
many times it's the 4-pin plug that plugs into the alternator you need to replace because it's that male/female spade terminal that doesn't grab the terminal inside the alternator tightly. google 4-pin alternator plug for GM alternator (CS130D is alt. model) they are easily mail ordered.
with your oem plug on the wire, there's sometimes no way to tell if the electrical connection is solid when it plugs into the alternator, the plastic connectors might plug in to each other well but you don't know what's happening electrically. so i would just spend $10-20 on a new alt. plug at the first sign of problems.
