Lights Flicker Only When Low Beams Are ON

[Spanky_DSM]

Ok, this is my 4th alternator from Oreillys with in 2 months and is the only one i have received that is putting out the 13-14 volts during idle and cruise. All the others the car would have do be under decent load to provide a decent output aside front battery voltage.

Only issue i am having is my lights flicker when my low beams are on. Revving around 3k rpms is when the issue begins.

Other wise i wont have any flickering.

Could this alternator be junk?
I have a new battery as well with brand new terminals.

 

[ThunderChild]

I think you need to check all your grounds and clean them

 

[luv2rallye]

Measure voltage at the flickering lights when it happens. Also check wires and for bad/loose wire connections. Do both flicker or just one? Taillights too?

 

[Spanky_DSM]

Interior lights and exterior lights flicker once the headlights are on and giving the car a decent throttle load.

 

[jimsgsx]

I have the same exact problem and its been pissing me off for a while now. I have checked every ground and cleaned them all. Didnt help a dang bit.

 

[luv2rallye]

I would first suspect a loose connection that makes and breaks the circuit with the vibration of the engine. I would start with the headlight and taillight relays. Do they flicker with just the marker lights on (taillight relay)?

 

[Spanky_DSM]

I would first suspect a loose connection that makes and breaks the circuit with the vibration of the engine. I would start with the headlight and taillight relays. Do they flicker with just the marker lights on (taillight relay)?

no only with the low beams on. i can have the tail lights on with the markers on and low beams off and wont have the issue, but as soon as the low beams are on and rev the car all interior lights, such as dome, low beams, tail lights, and cluster ill get the flicker.

 

[Spanky_DSM]

Im really suspecting the alternator but am hoping there is another probable cause. It wouldn't do this with the other alternators but then again i would get 12.4 volts when idling and 14 volts under load with the other dud alternators.

 

[luv2rallye]

Well if it wasn't doing it with other alts that seems to point to this one. What voltage are you getting at the battery at idle and under load? Also have you checked the tightness of the alt belt? If not tight enough it can cause this.