As I start in the morning the battery light comes on and as I checked the alternator does not put out. I drive some with the light on and it does not go off. I stop and turn the motor off then restart and there is no battery light on the dash any more. That time I checked it out with the voltmeter and Alternator works fine. I tightened the tensioner pulley but it did not help. Once a while I here some tapping noise coming from the passenger side of the engine, mostly when I first start. I am sure it does not come from the motor itself (valves, lifters). It may be coming from that tensioner pulley. I can't tell.

Is the alternator going bad or is it something else. How to go about checking it.

Thanks

 

Many if not most auto parts stores can check your alternator if you can pull it off and bring it in. Call first and see if they can do that. It could be that it's on its last legs and intermittently failing.