belts

I'm having a strange issue with my '95 Park Avenue where it will routinely idle low when in park, reverse, or neutral. I recently swapped out the battery, alternator, and starter since the old alternator which was in the car was not charging the battery when I drove; I was having low voltage...

I was wondering if you could spray lubricant behind the Belt tentioner on a 3800 v6 2003 Buick lesabre just to do it for preventive maintenance ? I know there is a spring behind it and sealed bearings so it would be more for the spring to move smoothly?:blink: