I have a 95 Blazer with a V-6 4.3CPI. Recently, I've experienced loss of top-end accelleration. It starts and idles fine, but with intermitant rattling from underneath similar to torque convertor noise, but not continuous, and possibly from the catalitic convertor. Also running slightly higher than normal temp, oil pressure is normal, no signs of moisture in the oil(which was also change 2500 miles ago). I cleaned the plugs and air cleaner about 300 miles ago. When I did, I noticed oragish coloring on a couple of the plugs, but no major build-up or signs of fowling. It's not smoking, or giving any fowl smells from the exhaust, but I do notice some condensation drippage from the tailpipe. The check engine light hasn't come on. Does anyone have experience with similar symptoms from their truck?

 

Sure sounds like the cat has broken up and gotten clogged.

 

Thanks for the response. This was one of my guesses, thinking a head gasket may have a small enough of a leak not to cause immediate running problems, but causing moisture into the catalytic, restricting exhaust flow. But, not sure and looking for other input before tearing into the top end without needing to.