When I blip the throttle on my 00 Firebird with a 3.8, the electrical in the car dims for a sec around 2k rpm then goes back to normal. The battery is brand new. Does not have this problem when accelerating, only on the decel.

Any ideas?

 

Just a thought, but when the engine suddenly decels, maybe the belt tensioner is unloading and the alternator slows down or even stops turning. Should be an indicator on the tensioner assembly that shows if the tensioner is operating in the correct position.

 

Fred-

I actually ended up replacing the tensioner assembly when I did the lower intake manifold gasket. I have not experienced the issue again so I would say we have a confirmed kill.

Thanks for your assistance.

Paul