I drove from New Orleans to Biloxi Mississippi on Saturday for the Skynard concert. It's about an hour and a half drive. Everything was fine until I got to the arena. I sat in traffic there for about 25 minutes not moving. The AC was on at the time. The temps crawled up to about 150-155 and the light came on. I shut off the AC and turned on the heater which did not help at all. I shut off the engine and let it cool down as soon as I noticed it. I know my passenger cat started dieing about three months ago due to an obvious rattling noise. At the start of the trip on Saturday I happened to be checking my rearview while changing lanes and accelerating. I noticed a bunch of crap fly out of the rear passenger exhaust. Also on the way back home a friend was in the car behind me. She called and said that something like a rock came from my exhaust and cracked their windshield. I slowed up and sure enough their windshield was chipped. I have not yet checked my fans to see what temp they come on or if they are working correctly. They are set by PCMFORLESS. On the way home the temps were fine. I am thinking that this may be due to a clogged cat. Has anyone else experienced this? Do you think a clogged cat will make it overheat like that. It is at the shop today getting my headders and cat delete/extensions installed. My coolant was completely flushed and changed by me around October. What is in the inside of the cat? Is it hard enough to damage anything? By the way the concert was great.

Thanks

 

Overheating engine isnt usually the symptom, you'd likely notice a big dropoff in performance or a rotten-egg smell. Overheating the footwell is a symptom.

 

the "rock" was part of the matrix that makes up the cats internals.

they do wear out, and they will throw chunks.

I will warn you... headers and no cats is going to make for one loud assed vette.

 

When my main cat went out ,perfect start /idle /no overheating ,just engine would not rev higher than 3500.
As Bogus says headers and no cat( my current setup ) is loud if you like that but better have good neighbours