Big 3 Help

[homermacleod]

After adding the led brake lights and flex-a-lite electric fans, I noticed the voltage meter on the truck drop below 14, before it use to stay .5 to 1 bar above 14. Lately, it goes 1 -2 bars below 14 as soon as I turn on the parking lights and also drops a little more when I turn on the a/c and the e fans kick on. I did upgrade the alternator to a 140 amp about a year or 2 ago.

I started the big 3 upgrade this weekend with the ground wire from the battery to the motor. The voltage increased slightly and the meter remained steady. Yesterday, I added the ground from the battery to the fender and the power wire from the alternator to the battery. When I start the truck in the garage and it is sitting still, the volt meter is fine. However, when I start moving, the needle starts bouncing/ vibrating a little (back and forth between 2 bars on the meter). Also, when I rev the motor, the needle vibrates, when the motor comes back to idle, the dash lights dim and the meter drops 2 bars for a second and then jumps back to 14.

First, I thought it might be the ground from the battery to the fender, so I removed that wire and took it for a drive. I had the same results (needle bounces). Then I put the ground back and took off the power wire. The needle bounce disappeared. I could rev the motor and the needle would not drop and the lights did not dim.

Does anyone have any ideas on what I might have done wrong? I used 0 gauge fosgate OFC wire.

 

[DRAGGIN95]

I would use an ohm meter and check the resistance on the alt. power cable that you made, sound's pretty strange.

 

[homermacleod]

I will check the resistance power cable tonight.

Just for the hell of it, I disconnected the stock wire from the alternator and just had the 0 gauge wire from the alternator to the battery. The meter did not move as much while driving and the voltage drop/dash dimming problem when revving the engine disappeared completely.

 

[///RAGMC]

Make sure all the grounds are clean also I would clean all the monting points on the alternator to make sure you have a good ground

 

[homermacleod]

I would use an ohm meter and check the resistance on the alt. power cable that you made, sound's pretty strange.

I tested the resistance on the wire. On any of the settings between 2000k to 2000, I got a 0 reading. When set to 200, the meter bounced around. It would read .8, .7, .6, then jump to 15, 13, then back to .6. For the most part it just liked to stay between .6 to .8, but would occasionally jump to 15 or 13. I will try clipping the probes to the ring terminals tomorrow to see if the jumping around was caused by my unsteady handsl.

If it stays between .6 to .8 when I clip it to the ends of the wire, does that mean the wire is good?

 

[homermacleod]

Make sure all the grounds are clean also I would clean all the monting points on the alternator to make sure you have a good ground

I will do that tomorrow or this weekend.

 

[homermacleod]

Update: The ground on one of my HID ballasts was bad. I moved it to another location and everything seems to be fine now.

Thanks DRAGGIN95 and ///RAGMC