GMC Repair: 2003 GMC Yukon xl 2500 Loss of power and knock off, gmc yukon xl, 2003 gmc yukon xl

Question
I have a 2003 Yukon XL 2500 with 8.1L engine.  I experience a loss of power and occassional knock off while driving.  When this happens the battery light comes on.  After it knocks off, it is hesitant to start and takes at least two tries.  Any thoughts.  Thanks

Answer
Hi
I would have fuel pressure tested. Have the shop drive it with pressure gage attached.
If pressure stays good, have the Catalytic Converters checked. Most muffler shops will check a converter for free or for a very small fee.
I hope this helps.
Good luck
PAwl