S10 Blazer Cat

[kuminkoskia]

I have a 1995 S10 Blazer 2wd, with a 4.3 engine, The catalytic converter has been rattling inside from time to time when it is running. Today I lost almost all power, I think the catalytic converter is blocked. Has any one ever experienced this problem.

[MGoBlue102]

yes, the rattling is definitely the cat, the porcelain breaks up inside when its old and causes blockage of exaust. Loss of power is normal, definitely have the cat replaced. Keep a close eye on the weld when the company replaces the cat, it is very hard to weld the top of the pipe since there is only about a 1 inch space between the body and the pipe. If the company doesnt weld it right, you will have air leaking before it gets to the cat and cause all kinds of false emissions reports with your sensors. If your in a state that does emissions testing, you may not pass that test either.

[kuminkoskia]

Thanks MGo Blue,
I had the cat replaced and bigger than day, the old cat insides was loose rattling around like a big deformed marble in a soda can, when it gets pushed to the rear of the cat by the exhaust, low and behold it blocks the exhaust... I had the engine put on a scan and the EGR came up faulty, had that replaced, now the old Chevy purrs like a kitten and throttles up the RPMs like a champ, nice call, thanks again..
Cruising again in California.

[kuminkoskia]

Do cats go out after so many miles or is it because of the faulty EGR?

[cobra1]

they general dont just go bad.

if you run over something that would strike the cat hard enough, it can break the catalyst substrates.

an improperly tuned or misfiring engine is the cats worst enemy however. raw gas from a rich running/misfiring engine burns in the cat, causing it to operate at a much higher temperature than intended. this causes the substrates in the cat to melt down , which then causes blockage.

[kuminkoskia]

Cobra, thanks for the brief on the notorious catalytic converter. I as I am sure others have, know where it is located at however the nuts and bolts of the mechanism, are all Greek.
Thanks again, she is running like a spring bride, with the new cat and egr valve.

[MGoBlue102]

I forgot about that, right after my cat went out, I got egr readings too, had to replace the egr valve also, thank goodness the egr valve is right on top of the engine and can be done very easily. I think there is some relationship to those two things since one needs to be replaced right along side with the other when one goes bad.