I think the premature failure rate on Denso rebuilt alternators/starters are much lower than some of the rebuilts you get at the parts store. You may have been unlucky on this densor rebuilt part.

Pulsing lights means the voltage is fluctuating, so the question is how. Probably 95% of the time, the alternator is the cluprit. If you have a new one arriving, I'd install it. Other items can be the large cables to the batttery have poor connections or corrosion internal to the wire. A voltage drop test is a simple test with a basic volt meter you can try. You can also measure the voltage across the battery terminals while the engine is running with a large electrical load (turn on headlights, blower, rear defroster, etc).

The belt could be slipping, but I'd suspect you'd hear it. Inspect the belt for a lot of horizontal cracks when you go to change the altenrator. A broken crankshaft pulley could also do this.The crank pulley is a metal inner pulley and separate metal outer pulley with rubber gluing them in the middle. If you have some whiteout or a paint pen, you can draw a straight line from the center bolt of the pulley to the edge. Run the car, and look if the line has shifted.

Going for the alternator and inspecting the belt is a good starting point.

 

so I took the car to someone else this morning. his voltage test showed at 14.8-15.1. he put the new Denso alternator in and the Problem is SOLVED!

I cant thank you enough for your help and expertise on these issues. I really appreciate it very much!

bryan