Need help diagnosing engine noise and headlight pulsing

[Jayscout777]

Engine makes a grinding noise at 1300 rpm- 2500rpm and just had tensioner pulleys and belts replaced

Headlights and interior lights pulse as well
www.youtube.com/watch?v=iBixunPh5Ns

Btw in the video i only step on the gas for a second and the dial goes up then down and then back up without me doing a thing.

 

[mylovehx]

You sir need a new altinator

 

[Jayscout777]

Jf

 

[Jayscout777]

You sir need a new altinator

Shoot i had that feeling, do u think the alternator could be causing the engine noise or only the headlights?

 

[JeffBel]

I've seen this when timing is off

 

[Jayscout777]

I've seen this when timing is off

Sorry i really dont know much about cars, valve timing? An what would fix it? Thank u guys or the quick responces.