2002 chevrolet 2500hd has no power - 2002 Chevrolet Silverado 2500HD

The motor is a 6.0 and its got about 108,000 miles on it. Its not showing any codes but when its cold outside when it starts it will die if not given gas for a couple seconds then runs fine. Not sure if that has anything to do with it though. How do I check to see if the Catalyic Converters are stopped up. I seen something on checking the pipe temp in front of them and behind and that will tell u but not sure if thats right (its duel exhaust and has two Catalyic Converters). The motor is a 6.0 and its got about 108,000 miles on it. Its not showing any codes but when its cold outside when it starts it will die if not given gas for a couple seconds then runs fine. Not sure if that has anything to do with it though. How do I check to see if the Catalyic Converters are stopped up. I seen something on checking the pipe temp in front of them and behind and that will tell u but not sure if thats right (its duel exhaust and has two Catalyic Converters).

what you can do is see if either you can loosen up exhaust pipes at the exhaust manifolds, or pull your o2 sensors out , yours has 4 of them, pull the ones out in front of the Cats closest to exh man. you will have to unplug the wires so they don't hang and rattle around and get damaged. What this will do is creat an exhaust leak and a service eng light also, but this should be enough to tell if it has more power with them out, in otherwords it relieves the pressure some if the cats are pluged it gives the exhaust a place to beath being it can't make it through the Cat. It will be noisey but you should be able to tell if there is more power. Good Luck what you can do is see if either you can loosen up exhaust pipes at the exhaust manifolds, or pull your o2 sensors out , yours has 4 of them, pull the ones out in front of the Cats closest to exh man. you will have to unplug the wires so they don't hang and rattle around and get damaged. What this will do is creat an exhaust leak and a service eng light also, but this should be enough to tell if it has more power with them out, in otherwords it relieves the pressure some if the cats are pluged it gives the exhaust a place to beath being it can't make it through the Cat. It will be noisey but you should be able to tell if there is more power. Good Luck