The interesting thing is that this was a problem BEFORE AND after I installed the 7th Injector Kit. When the cat melts down, the 02 Sensor sends #s to the ECU that make it look like the exhaust gasses aren't being cleaned properly, so the air-fuel mix is adjusted accordingly. Eventually, the mix becomes so far out of whack that the engine doesn't have enough power to move the truck.
When the cats are beginning to melt, there are subtle losses in power that within 5-15 minutes of driving, make the truck essentially undrivable. Then when stopped the idle is very erratic, swinging back and forth from 1500rpm to 3500rpm.
If you look inside the cat at the damaged media (a ceramic matrix of thousands of small square "tubes"), it is definitely melted on the engine side of the exhaust, the other side seems to be relatively undamaged.
Although I can't be sure if this has anything to do directly with the cat meltdowns, there is a really weird behavior that my truck is exhibiting that could possibly be the cause. When I am at high RPMs for an extended period (maybe over 30sec) and then I go to accelerate, many times my truck momentarily stalls for about a second or less. This is occasionally violent enough to lock the drive wheels momentarily. Then, for about 5-10 seconds the available power tapers up from about 50% to full power. A good example would be when I'm getting ready to pass someone(therefore I'm running at high rpms), I wait until I get a chance to pass and then floor it. Has anyone ever experienced this before?????? I also street race frequently, but oddly enough this never happens then, as I'm never sitting at high-rpms for very long. My hypothesis is that this happens when the ECU is switching from the long-term fuel trim mode to the short-term mode, and it can't adapt quick enough to the huge demand for fuel or air. I'm not a mechanic though, so I really don't know.
As far as the guy at TRD that recommended the cat-boring, I don't want to get him in trouble or anything, however, the asshole at TRD that told me I couldn't have my supercharger anymore was the TRD Western Regional Sales Rep (Rick I think, and yes, this guy is truly an asshole). I was able to have that decision overturned by someone higher up at TRD, basically if I agreed to bore my cat out and use an 02 sensor simulator. Of course they didn’t say "if you do this, we won't take your supercharger off", they said I had one last chance and if anything else happens, you'll have to have it removed. They did offer to pay for the removal and reimburse me for the cost of the supercharger, but what kind of fix is that?!?!
I'd use the URD fixes, but I don't want to jepordize my warantee... Is there anything I can do that they won't notice or that I can remove easily for services?
Thanks for the help!